You ought to try sitting down in a restaurant in the EU. They do the bare minimum to serve you.
Tying a possible bonus to the way you act in customer service facing role has a lot of benefits.
"In addition it gets rid of any bias in wages (more attractive people more attractive people" Why are higher wages for a subjectively attractive person a bad thing... Are they not driving better business? Do you think it's somehow more altruistic to provide subjectively uglier individuals the same wage? Bias based on attractiveness is no worse than bias based on personality or any other trait. Your point is moot anyway, in a capitalistic society people can just choose to visit another business where the staff has the traits they desire.