I only say might because I haven't seen him for myself, but this is what I've been told. As for why ... you'll have to ask Damon Salvatore. Apparently he and this other hunter named Damian Jericho are hatching some kind of vampire double agent plan.

[Which ... Sam thinks that's questionable at best, but he also knows that Damian is working with what he's been given. He's always been good at that - rolling with the punches.]