To
Insure
Prompt
Service

This is really a silly debate that always seem to come up. Care for another opinion? If you have the personality to make tips work in your favor, great. If not, don't bust on the people that can and do. I know some folks may feel awkward in certain situations when they are not sure about whether to tip or not. I go out of my sometimes looking for tipping opportunities. You can question the morality of tipping for the next year and not still not have a definitive answer. If some people can use it to their advantage, let them be. If you don't like it, don't do it. It does happen so let's learn to live with it.