Why wealthy people oppose income taxes?

People who pay more tax that most will naturally oppose higher taxes. It's not that they oppose paying taxes as a means to operate the government but they see waste in government and don't wish to contribute to this. Less wealthy people oppose sales taxes often times because they see this as a tax that they have to pay. We are almost at a point in the United States where half of the people do not pay any income taxes. This means that instead of everyone paying their fair share of the costs of government, half of the people pay nothing towards their fair share. Certain politicians have used this as a platform to stay in office by pandering to those who pay no taxes by promising more programs and such to benefit the ones who pay nothing. In the United States we have a progressive tax system which means that the higher your income, the higher percentage of your income that the government takes to support programs that don't benefit you. Is this fair. This is the debate.