I took the "rich white people" term to refer to people instinctively unaware of their privileged position, to the extent that they don't see that things might be different for others. (For full rhetorical effect, to my mind, this requires both riches and whiteness, since one without the other doesn't have quite the same implication of breezy unthinking carelessness.)
Obviously having a Mac and working in San Francisco and treating Windows users like they don't really exist is not quite the same as being rich and white and never thinking of people who are poor and black (or whatever). But the parallels seemed pretty obvious to me.
I hope the poster doesn't get banned for their flagged post. It's good to see people fighting for social justice by calling out oppression where they see it - but I really didn't see it there myself.
