Your character hates rich people. Give him 3-4 lines of really nasty dialogue. Then, in two sentences or less, identify the specific source of his feelings.
Dialogue 1: "Oscar Wilde was right. 'No man is rich enough to buy back his past.'"
Dialogue 2: The rich are the people who have the money and the clout to write history. It's because of this that the poor are blamed for everything.
Dialogue 3: Yeah, yeah, yeah... So you're a proponent of simplicity. Well, I'll bet you my next paycheck that you started out wealthy. Am I right? Your money was there well before you decided that simplicity was the way to go. Makes me sick.
This particular character has been on the cusp of the poverty line since as far as he could remember. He does everything he can to save money, but there is just no way, so he is beyond incensed with the seeming good wealth of the 1%.
What did you come up with?