Because he's mafia.
So Dema, how do you feel about lynching Onion tomorrow?
Wouldn't it be easier to kill me tonight?
That's just not quite as fun.
Also we need to find out who has the other rock. Sera?
IMO all of you are equally likely to be mafia. I have my suspicions, which I believe I've already made clear. Town is starting to throw the game with no lynches though, so w/e. Let's just lynch someone and play the game.
You say his play doesn't make sense as town, but I can't think of anything off the top of my head. Give us some examples.