I went to undergrad college with some extremely well off individuals. I can't say that they were actual billionaires, but in some cases, their last name was that of well known corporations. Of course, we never talked about money.
I would say that they seemed like everybody else, in that the college was a very expensive private liberal arts college on the east coast. But the couple that come to mind did have a little trouble fitting in.
It's hard to put your finger on it, but there was a sense that they were different. It did create a little awkwardness for them or so it seemed.
FWIW, i was only able to attend because of a tuition waiver for children of the staff, if they got accepted. I was by far the poorest kid there, and came from a family that probably would have otherwise struggled to put me through a public college. I caught a lot of crap. LOL.