Tipping was never meant to be a reward for EXCELLENT service. Tipping is in return for service. Excellent service would demand more than 15% in most cases.
You take a 5 star restaurant, you are usually served by a staff of waiters/waitresses...you are rarely waiting for anything. The food costs are higher, so that standard 15% is a bit. Service here should be better than the average to sub average restaurant most Americans (at least) seem to frequent and expect a red carpet to be rolled out for them. If you are paying only $5-7 for an entrée, you can't expect your drink to be always full unless you stop your server from time to time. These people are given more tables than normal to offset the lower food costs.
Problem is, is that 15% tip is still customary for them merely servicing you. If you don't like the service complain or do not go back. Just as an employer still has to pay a person for what they have already done even if they are firing them.
I personally think many that complain about the tipping system are either living beyond their means and should be eating food they have prepared themselves at home, or think they are the next 'J-Lo' or 'P-Diddy' and feel they are above common etiquette.
Yes, at least in America, the tipping system is designed as a form to 'top up' wages, but it was never meant to define service above and beyond customary for the level of establishment.
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