HAPPY HOUR used to be so much simpler.

Picture a couple of co-workers, crossing the street for a cut-rate well drink or a beer at the nearest bar, taking the edge off a stressful day.

Maybe they'd have a cheap snack, something to soak up the alcohol. Chicken wings, say, or potato wedges. A quick bite to fill the gap between work and dinner.

If wine was considered, chances are it was a minor player, with two options available by the glass: jug white and jug red.

Flash forward to today's happy-hour scene: Chicken wings are still out there, but nearly lost in a swirl of sliders, calamari, spring rolls, ceviche and scaled-down portions of regular restaurant entrees.

Happy hours, some starting at midafternoon, stretch into the evening. Others reappear in the last few hours before closing. Some are assigned entire days.

"For a lot of people today, happy hour is dinner," says Chris Myers, wine director at Aqua by El Gaucho (formerly Waterfront Seafood Grill), where a happy-hour customer might chow down on the $7 halibut ceviche in the bar, served in a glass tumbler with tortilla chips on the side, instead of the $38 grilled Alaskan halibut entree on the dinner menu.

Even the casual observer of Seattle's happy-hour scene has noticed the proliferation of specialty cocktails described with six or seven adjectives (infused this / muddled that) and every bar in town, it seems, touts its own take on the mojito, martini, Manhattan and margarita.

But as food has become more important at happy hour, so has the beverage many diners consider an integral part of a nice meal out: wine.

Whether it's a flute of Prosecco with sweet, briny oysters on the half-shell, a crisp pinot gris with a mildly spicy prawn cocktail or a deep Washington cabernet sauvignon with a small cut of beef, never has a wider array of wine — from our own backyard or the other side of the globe — been available by the glass, often at discounted prices.

"I'm tasting new wines every week," says Dana Hannon, owner of Smash Wine Bar & Bistro in Wallingford. "The average customer is becoming more educated about wine, and people want to try different things."

NOT ALL that pours scores, warns Chris Horn, wine director of Purple Café and Wine Bar's Bellevue location. "The problem with many so-called 'happy hour wines' is that they're not any good," he says, noting that some distributors, in the lists they send to restaurants, simply promote their very cheapest wines as happy-hour fare.

So, Horn says, just because you can find a $3 glass of wine at happy hour doesn't mean you'll like it.

For a restaurant, having customers nibble in the lounge for a fraction of what they might have spent in the dining room is not a perfect world. But due to evolving customer preferences, reinforced by a shaky economy, it is the one to which they must adapt.

"These days, if you don't have a happy hour, you're shooting yourself in the foot," says Hannon, who opened Smash five years ago without a happy hour, but soon saw that if she didn't attract happy-hour patrons, someone else would.

She offers a changing lineup of wines, always including a red, white, pink and sparkling wine for $5.95 a glass. Happy-hour food plates typically range from $4.95 (think beef sliders or potato cakes) up to $11.95 (crabcakes, clams with tomatoes, truffled mac & cheese).

In addition to its happy-hour picks, Smash entices guests into exploring wines by listing 10 three-glass wine flights — most between $15 and $20 — exploring a common theme, such as "He Who is Without Zin," a trio of California zinfandels.

At Aqua by El Gaucho, where the regular wine-by-the-glass list tops $25, glasses of happy-hour red and white wine are $5 — and the white wine, a Chilean chardonnay (Viu Manent), has become the restaurant's most-ordered item, food or drink.

"Happy hours are all the rage," says Myers. "People want to know where the deals are, and you really can't blame them. We've had to adjust."

That adjustment has included a 4-ounce steak with narrow-cut fries for $16. That's $2 less than an Aqua dining-room patron may pay just for the "oscar" topping (béarnaise sauce, crab and asparagus) to layer over steaks topping out at more than $60.

Myers views happy hour as an audition for the restaurant: If people like what they see, taste and experience, they may come back for a longer, larger meal in the dining room. (On payday, perhaps.)

That's also the thinking of Jill Buchanan, who opened Lecosho on the Harbor Steps last year with business partner Matt Janke. "Happy hour offers a small showcase of what we do," she says, a repertoire that includes small plates of pasta, sausages and cured-meat dishes made on the premises, such as the $6 rillettes of braised pork belly terrine.

Happy-hour guests at Lecosho — which draws a clientele from nearby office and condominium towers — can choose a $4 glass of red, white, sparkling or rosé wine, or peruse a larger list offering wines by the glass for $8 to $12, along with 10 specialty cocktails.

Lecosho's regular wine list includes a sampling of Northwest wines, but the inexpensive, food-friendly wines at happy hour are likely to be European, such as French rosés and Italian reds.

JUST HOW much should a restaurant mark down its wine at happy hour?

Maybe not at all. Toulouse Petit Kitchen & Lounge on Lower Queen Anne is among restaurants that, instead of discounting wines, draw happy-hour trade through the breadth, depth and value of their small-plate offerings.

Boldly printed across the top of the New Orleans-influenced restaurant's happy-hour menu is the claim that it's the best in the nation. As evidence, it presents more than 50 dishes in the $4-to-$8 range, including lamb sliders ($5), fried catfish sticks ($5) and crab ravigote over fried green tomatoes ($8).

And even though wine prices don't dip at happy hour, the list does include more than a dozen glasses at $8 each.

Jason Crume, Toulouse Petit's wine director, says people don't need — and may not even want — a cheap wine at happy hour. He relates an experience he had working a wine bar a few years ago:

"I found this amazing Chilean pinot noir for $6.95. And I tried to pass the savings along by charging $7 a glass. That's kind of the industry rule: You want to get the price you paid for the bottle back on the first glass.

"But nobody would buy a $7 pinot noir," he says. "I raised it to $8, still nothing. Then I raised it to $10 a glass and sold a case the first week . . . Pinot noir can be a finicky grape, and no one believed you could offer a good one for less than 10 bucks."

In Seattle's vibrant happy-hour scene, where beverage choices abound, the role of wine varies with the type of establishment.

At fine-dining restaurants such as Aqua, food is typically still the driver, with wine selected second. At wine bars, such as Purple Café and Wine Bar, patrons may select a wine first, or opt for specific food-wine pairings suggested on the menu.

And at some casual restaurants with busy bar scenes — Toulouse Petit would fall in this group — the rules of pairing wine and food may be simply tossed aside. Thirsty customers may pick a favorite beverage first, then settle in with the menu to add whatever morsels tempt the taste buds, often sharing plates around the table.

AT THE BUSY corner of Western Avenue and Virginia Street, on the north edge of the Pike Place Market, a red neon crab in a window marks the site of 1-year-old Seatown Seabar & Rotisserie, part of the burgeoning Tom Douglas food empire, which now boasts more than a dozen Seattle locations.

Inside, one can see evidence of a trend: Wines pumped from taps, instead of being poured from bottles.

At Seatown, four wines — two whites and two reds — come in metal kegs, like beer. Nitrogen is pumped in to force out the wine "and the wine doesn't hit oxygen until it comes out the tap, so the last glass can be as fresh as the first," says Seatown general manager Gretchen Geisness.

Geisness says the process is "greener" than bottled wine because it cuts down on packaging. Some kegs go back to the wineries to be refilled. Others are used once and the aluminum is recycled, like giant beer cans.

It's a money-saver for wineries, distributors and retailers, because a single 30-liter keg holds as much as 40 standard wine bottles, with lower labor costs and less storage space. Geisness estimates the savings at roughly $2 to $3 per bottle, enough to bring more wines down to happy-hour price points.

Seatown's happy-hour list features a pinot gris, pinot noir and cabernet sauvignon, all from Northwest wineries and each going for $7 for a quarter-liter decanter (about a glass and a half).

Although wines on tap are becoming more popular here, Seattle lags behind San Francisco and Portland in their use, Geisness says. And it doesn't work for every establishment: Bars that want to offer as many draft beers as possible may not want to spare the taps.

AT THE BELLEVUE "Purple," food-wine pairings are a major focus of happy hour. Wine director Horn loves exploring unexpected combinations, such as accompanying a rich chicken paté with a dark, sweet dessert wine from Spain.

"When you combine a liquid and a solid and come up with a flavor neither had by itself, that's exciting," he says. "That's what we shoot for."

Horn holds regular classes to educate the restaurant's staff about wine, and sometimes passes around glasses of cloves, cinnamon sticks, allspice, nutmeg, coconut or other foods and spices. He wants servers to discern the aromas they might encounter in a glass of wine, so they can help customers decide what to order.

Happy hour should be a time for fun and adventure, says Horn, who recently began offering several $7 combinations that include small portions of cheese, fruit and a half-glass of wine. He intends to change the lineup frequently, so returning guests find new tastes to try.

"When they come in for happy hour," he says, "we want to get them hooked on the experience."

Jack Broom is a Seattle Times staff reporter. He can be reached at 206-464-2222. John Lok is a Times staff photographer.