I doubt if this is what @PurpleTitan was thinking, but in my area (rural midwest), asking what high school someone went too is quite common. After all, most people here are living within 50 miles of where they grew up. There are of course some outsiders (like me, from a whole state away! People still ask though.)
BTW, I went away to an Ivy and honestly, my HS comes up much more often than my university degree. And I totally agree that it is normal here to hide going to an Ivy. It is very rare, and people often get weird when they find out.