Agree! I think there is basic concept problem here.When you serve customer as a waiter or waitress, you need respect your customers then you will expect your customer to respect you, if your feeling was not balanced, you better not doing the service job. For my observation these peoples only interested in your tip and did not think how to improve their service, and some service person even believes my class level is high than you. if you have such feeling how do you expect customers will tip you. of course you will lost your customers. This is very simple.
Around last Christmas, the frinds of mine and my family went over there for dinner. After I got some bad experience, I decided I will never go back again. the food was ok, but the sevice was unacceptable, the waiter over charged our food.