Additionally, I'm not going to pretend that Greek life is 100% free of douchebaggery. Some people in fraternities do bad things to other people, or harbor bigoted worldviews. I feel that you grossly overestimate the proportion of people who do. To address the racial and sexual homogeneity point, I'm fairly confident that every single fraternity at my alma mater had individuals of color and homosexual individuals. My own certainly did.
I'd also like to point out the obvious blanket statements you've made about the demographics and attitudes of fraternity members. However, I really don't think anyone or anything can budge your opinion.
While I accept that some social associations may have disturbing incidences of systemic problems that must be addressed, I strongly disagree that it is OK to make judgements and assumptions about individual people without knowing anything about who they are as a person.