Kind of an odd question, but when Chip hops on the train, and see's the hobo in the back - Is that Galifinakis playing the hobo?
It looked like him and would not surprise me if they did that.
I think it was Chip seeing his own possible future. The whole "jumping on a freight train" is obviously an escape... and I think the next logical step for a (mentally handicapped, I guess) person like Chip, in this scenario, would be living like a hobo.
It's sad, and it's a huge decision for Chip! I think this ending was perfect.
Also a perfect beginning for season 2!
Zach was probably not the actual actor... but the hobo was obviously supposed to look like him. Also, notice there was a second hobo in the dark behind the guy. Maybe Chip ends up finding a new friend...?
(The man in the dark looks like the other clown from the Rodeo, Bingo or something... But that's probably stretching it)