A drive-thru margarita bar might sound a little, well, illegal. After all, open containers aren't allowed in any state in the U.S. of A. But there are loopholes, and through those loopholes pops up Houston's W Grill and its delicious frozen concoctions.

At this neighborhood spot in the hip Heights neighborhood of Houston, you can sail into the drive-thru on any given day and head home with a slushy cocktail. It's your choice of a piña colada, a cherry margarita, a mudslide, or any number of other boozy treats. But, you might ask, how exactly is this legal?

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According to the drive-thru waitress, the tape on the lids keeps the po-po away. By taping the sippy part of the to-go cup, they've made the beverages transportable.

This isn't just a Texas phenomenon. Drive-thru daiquiri bars are hugely popular in Louisiana -- and parts of the Sunshine State have drive-thru liquor stores.

W Grill also serves food, but according to the spot's big, bold roadside sign, it's mainly about the margaritas. There's even a hashtag: #margaritastogo.

Twenty-ounce rita flavors include mango, strawberry, cherry, peach, blueberry, sangria, and key lime pie (how very Floridian!). There are even 100-calorie "SlimRitas."

Foodstuffs include jalapeño burgers, hot dogs, Philly cheesesteaks, and other sammies and sides..

The frozen drinks are a tasty treat, à la Wet Willie's, but I imagine they're a little too tempting for some drivers to have a delicious slushy mudslide riding alongside them on a boiling-hot Houston day.

And frankly, with the state of traffic in that massive urban sprawl, it's hard to imagine they wouldn't melt on your ride home.

But if you're packing for a nearby tailgate, planning a picnic, or just don't have access to a good blender, it doesn't get much more convenient than drive-thru margaritas.

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