Well, they did in Weatherford. They do here on NPI. They did in Ft Worth when I lived there before moving to the island.
I mean, yes, LEGALLY, the restaurants have to ensure they make $7.25/hr so if their tips don't add up, the restaurants have to do that. But, most restaurants still do the $2.31/hr + tips model which most times means the servers make a lot more than $7.25/hr. I'm the one paying for their labor for the most part through my tip. Which is perfectly fine with me. I pay for the service I get because I know it's not baked into the cost of the meal.
But, if the government mandates a MW of $15/hr, then the model has been changed to where the restaurant is paying for their labor and then including it in the cost of the meal. Now I don't feel like paying for it in addition to the restaurant paying for it. Maybe I'll toss in a small tip for extra good service, though. Rewarding the ones that go the extra mile. But, not my standard 25+%...