Bruce Horovitz

USA TODAY

Milkshake lovers now have an excuse to toast before slurping — the wine shake is in motion.

Red Robin, which claims to be the first national restaurant chain to roll out beer shakes two years ago, now is turning to wine shakes as something a bit more sophisticated, expensive and, perhaps, buzz-worthy.

It's just beginning to sell the Mango Moscato Wine Shake — made with wine, vodka, mango puree and vanilla soft serve — at its 480 U.S. locations.

They aren't cheap. The shakes, mostly targeting 35- to 49-year-old moms in need of a break, sell for $7.49. That's only about a buck less than many of the chain's gourmet burgers. Denny Marie Post, the chain's chief marketing officer, says it's all about Red Robin "continuing to stay on the leading edge of fun trends."

It's also about luring in customers. The restaurant industry in general — and casual dining in particular — has had a rough go the past several years as the economy has wobbled.

Beyond price-cutting, one of the best ways to attract customers is with gee-whiz products that aren't widely available elsewhere — even if most customers don't buy them.

It's also a matter of timing. Spring is when many restaurants begin to roll out limited-time cold beverages for summer. Red Robin is making a mark with its alcohol-infused shakes. Two years ago, it rolled out the $5.29 O'Fest Beer Shake. And it's got more wine shakes on tap.

"These products are more for show than for blow," says Gary Stibel, CEO of New England Consulting Group, which consults on the restaurant business. "It's badge value for them." Because the wine shakes are unique, he says, they're also prime fodder for social media buzz.

But objections already are being raised by at least one alcoholic beverage industry watchdog group. "It's alcohol on training wheels," says Bruce Lee Livingston, executive director of Alcohol Justice. "It's an attempt to get a younger market drinking."

Not at all, says Post. The alcoholic shakes appear in a separate section of the menu dubbed "Adults Only Boozy Shakes." Customers have to be 21 to order them and will be carded, she notes. And they're not served in conventional milkshake glasses, but in smaller cocktail glasses.

"We're not a big party restaurant," says Post. "But for a mom to enjoy a wine shake with a burger is reasonable — and fun. It won't be one of our highest-selling item, but there will be people who love it."

Among them: Stibel, the consultant. "These things are outrageously good," he says.

That drives Livingston, the alcohol industry watchdog, crazy. "They're just trying to find ways to get people to consume more alcohol," he says. "It's about the money."