That whole Sam thing at the end... it confuzzled me so much. Even after watching it twice. On the third go, though, I picked out that Dean says something about "seeing US run around in monkey suits". YAY! Concrete-ish evidence! Now, I'm gonna say that Sam was real cuz it makes me feel happy XD but I still find it oddly odd that Zachariah didn't even mention him at all, on top of not having him show up. Meh.