Wasn't a key point of A Chorus Line that -- fair or not -- these people are never going to be famous because, good as they are, they 'blend in', no matter how talented?
I have been attending the theatre for 50 years, and I don't think I have ever once known the name of someone in the ensemble, unless they had something approaching a solo, which brought them special attention, and there really weren't that many.
I suspect they know Thayne Jasperson for three reasons: (1) he has a solo, although it is on the short side; (2) he is one of the only Caucasian members off the cast, which triggers a 'what is he doing there' reaction; and (3) he is very good looking. I could mention Donna McKechnie from Promises! Promises!, but the only reason I became aware of her name was because of her work in Turkey Lurkey Time. Similarly, he only reason I know Harvey Evans is because of his role as Young Buddy in the original Follies, not his ensemble work.
I am not trying to come across as a Grinch here; but, unless one is a theatre insider, which I am not, I just don't think there are famous ensemble members.