I would think the individual franchise owners would be on the hook for this, but deep pockets rule.
I've heard McDonald's workers complain about some of them. You'd think McDonald's HQ would have a process to deal with complaints. Then again, they're McDonald's employees....the good ones can always go to another restaurant or grocery, with many of them paying better wages.
There are always crooked people out there, I was aware of one franchise owner's son who would cheat people because he knew they were illegal and afraid to complain or just plain afraid of losing their job, my people would tell me about their friends and I always told them to tell their friends to turn the guy in, cheating people is just evil.