Exactly my point, if we decide that the rich should pay more taxes because they earn more, then it would become natural for them to be entitled to more benefits from the government compared to the poor. It is all about equality, as long we all believe to be equal citizens of a state, we should all pay the same tax levy.
It would be terrible if the tax percentage changes just because one person is richer than the other. I wouldn't support such an idea because I don't expect myself to be an average person financially forever. I will become rich one day and whatever I decide to will also affect me.