> The reason being is that, not only are you almost certainly wrong, but it doesn't matter.
I've noticed that, in this field at least, everyone does come from a much more wealthy background than I do. I once talked about my experience of working at McDonald's as a youth once and got a lot of weird stares. Kids of doctors, professors, etc...I think it is mostly because they went to good schools in the first place, there aren't that man poor kids that go to CMU or Stanford. Heck, it is much worse at the PhD level.
The other points are valid: given the talent shortage in our field, they mostly don't care about your background. It is much more relevant during promotions in dysfunctional orgs.