Yep as always. There's a reason these people working minimum wage jobs aren't exactly the brightest or have a great understanding of basic economics.
The only thing that this will appease is the ego because everyone else is going to suffer because the companies are going to raise everything else to offset the increase not to mention these people are really just going to have their jobs eliminated all together.
What are the odds that a fast food place really just lays off a ton of people and then overwork the hell out of a few remaining or just create automated systems or close down the dining areas all together?
And if a food service employee can get $15 guaranteed then what should every skilled or educated person in a better job get? By that logic, you raise everyone's pay across the board, which won't happen.
If they'll pay me $15 per hour to flip burgers I'd do it just to supplement my income. That said, why wouldn't they hire a guy that has multiple degrees, has demonstrated himself to be responsible and reliable over some kid or hs drop out? There will be MANY unintended consequences such as this. Jobs that are not attractive to "better" employees will become so....leaving lesser paying jobs for the less qualified. Hey, maybe I'm for it after all