The United Nations also has figured significantly in American history, and is a conduit for execution of foreign policy initiatives, regardless of which party is in power.
It's important that people know about such people and institutions. It's part of being informed, whether you like them or not.
You're really right about having to own property to vote, though. For a number of years, I lived in government housing projects, didn't own my own home, yet I was able to vote anyway. Outrageous! Those projects were totally at taxpayer expense, housing thousands of non-property-owning people like me, who still got a vote, at places like Fort Hood, Fort Riley, Fort Benning, etc., etc. Why should folks living off the government and not paying property taxes expect to have any say?