Why do the characters have Ivy league, resume names?

That says a lot about you just for asking this question. Why do those have to be Ivy League names? Get out of the ghetto!!!!

There are actually black people who give their kids "normal" names. I have black friends or acquaintances named Jordan, Lance, and Robin. Shelby is kinda old-fashioned, though. I got no problem with it, though.

Most people I grew up with had these types of names. I guess I can sort of see your point when a lot of black people have the names in your second list or closer to those than in your first list.
I'm thinking that since the characters are all college educated or have at least attended college (Robin's interests jumped around as the guys joked about) so the names are to reflect that.