Observation from the U.S.

Whilest visiting that lovely country I noticed a very unlovely habit , that of tipping servitors ( waiters and waitresses to us ) , I was told that the going rate was a tip of 20% for good service , 15% for mediocre service and 10% for poor service . I am at a loss to see why the customer should pay , by tips , the staffs wages , that surely is the responsibility of the establishments proprietor . It demeans both the worker and the customer , turning the waiter into little more than a beggar , something that no one wants to do .
Here in the U.K. I do tip for good and considerate service , but in cash terms ie between £2 and £5 for a meal for two ; however if the service is less than what one should expect then no tip is given , I do not think that it is an unreasonable position .
It is unlikely that this post will do very much to change things in the U.S. but one has to start some where and hope that the liberation of waiters and waitresses starts here .