Let's not play that game. As a former cook, I can tell that yes, there are lots of immigrants. Most of them work unbelievably hard, and really, really depend on these jobs to survive.
There are also a _lot_ of addicts, psychopaths, morons and other assorted human detritus, of ever conceivable hue competing for these jobs, which also depresses wages.
Furthermore, restaurants don't have any damn money. Restaurants are on razor thin margins always. Usually a bad week or two from going under.
Qualifications for working in the kitchen consist of:
1. will you work for very little money?
2. can you work ok when you're high and/or drunk?
For fancy places:
3. can you safely handle a knife?
4. will you toil endlessly for no apparent reason?
That's pretty much it.