I was watching and kept on saying to myself it was Erik Seidel but it didn't make sense. I'm glad someone confirmed it. It's great and it was a classic episode. I like that Erik was an extra and had no speaking part. That's what made is surreal.
Seidel knew. I don't know a lot about film but I'm pretty sure they secure locations before shooting. They pick and choose the extras. Its not random afaik.
So he paid (even though the money went to charity) just to be visible in the background in a non-speaking part ? I guess those 4 others laid down some dough as well ?
Also about Ben Affleck, I thought that guy from the movie was him too. I saw it twice though and thought the same thing each time. *That* seemed far fetched though and I wrote it off as a lookalike. He is a poker afficianado also, but I think if he'd be on Curb he'd play a much more prominent role.