I’ve dated Waffle House waitresses in the past. They make more money than you think. As to high-end (or even mid-level) steakhouses. I made so much in tips as a part-time bartender at a “Steakhouse and Saloon” type business near a capitol city airport (I also got 20% of the waitresses tips) that I almost never cashed my hourly checks, even though my hourly pay was over $6/hr. and just let them accumulate.
I supported my family and my first child for several years bar tending 4 nights a week. So it can be good money. As for some Waffle House folks doing well, I'm sure they do - but the vast majority of diner staff make far less than the vast majority of upper end restaurants. It's a hierarchy as you know - you "move up" from A to AA to AAA to the majors so to speak.