There’s no basis for insisting that one must be poor to work for the interests of those less…
Peter C

While it is possible to mention a handful of rich philanthropists, it’s been well established that rich people tend to be less empathetic, according to Scientific American.

Given the growing income inequality in the United States, the relationship between wealth and compassion has important implications. Those who hold most of the power in this country, political and otherwise, tend to come from privileged backgrounds. If social class influences how much we care about others, then the most powerful among us may be the least likely to make decisions that help the needy and the poor. They may also be the most likely to engage in unethical behavior. Keltner and Piff recently speculated in the New York Times about how their research helps explain why Goldman Sachs and other high-powered financial corporations are breeding grounds for greedy behavior. Although greed is a universal human emotion, it may have the strongest pull over those of who already have the most.
Paul Piff: Does money make you mean?

When Bernie supporters point to conflicts of interest between her purported desire to help the environment, get tough on the big banks, reduce incarceration rates, and reduce the cost of a higher education while accepting money from parties which have a vested interest in making sure those goals do not come to fruition, this is not done out of malice. It just so happens that the Clintons have become extremely wealthy pushing for policies which, by and large, hurt the poor and middle-class.