That Fred Armisen is a real asshole in person.
I didn't really interact with him at all, but we both attended the same wedding for a mutual friend and he was extremely off-putting in person. He arrived late, underdressed, and very clearly thought of himself as being the center of attention, despite this being a day set aside for the specific and exclusive purpose of celebrating two other people. Maybe that is just what it's like being a celebrity at the wedding of the hoi polloi, but nevertheless, I understand why people describe him as creepy.