The majority of our income taxes are paid by very high income people. They may also feel that if we tax them too punitively they'll leave or cheat or have less money to start/maintain businesses, etc.
The top marginal tax rate is about %40 right? It used to be 90% in 1960 and 70% in 1980 although these kicked in at much higher amount of wealth than in the modern day. What do people think is 'fair' considering most do not even understand progressive taxes. 100 years ago there was no income tax.
I personally think we spend too much and the main reason I support higher taxes on the rich (especially cap gains over a certain amount) is so it is not as easy to subvert the political system in their favor. I don't know what number is 'fair' though.
A Straw Man
What kind of person worries about raising taxes on the rich that cannot pay back taxes and is underemployed? A temporarily embarrassed millionaire. I've lost track of how many people I've met who can barely make ends meet or are deeply in debt and yet hold onto this philosophy.
Isn't it a good thing that people have hope? Yes. But is it a good thing to live in a fantasy world and make decisions based on that fantasy while failing to live up to your obligations in your every day life? No, I think it is a terrible thing. A significant portion of Americans seem to live in a state of delusion. It's stupid for people who are un or under-employed and have no capital to vote for and advocate for those making millions because they themselves think they will get there eventually. This seems to happen quite a bit in America and nowhere else.