Not sure what happened there, but it could be he was looking for a/or specific class(es). But then you might ask why he didn't just list the class/classes he wanted or such, and I can't really answer that. Maybe he just wanted to be an a-hole.

How you react to this is up to you, though I feel you'd be the better person to simply let it slide, and perhaps politely decline his offer to allow him to join your party if you ever so happen to start one.