because we've done it before. The trick is not minding, and therefore never answering him. It's called the silent treatment, and it worked a treat last time. I indulged once, but I've kept out of it since then... except to make this very same point.
Folks, if we don't want him here (and I pretty much don't; the shit he pulled on Owl alone is reason enough, let alone his online behaviour), we gotta stop responding to him.
Lily, having known Norm in an online way for quite a few years now, I'd call it borderline personality disorder... but I'm not a doctor. OTOH, I've read about sociopathy a fair bit and the shoe fits... it's just fortunate that he's not way way off the scope and not hugely competent along with it, and therefore ends up being less than functional instead of a monster. That didn't stop him from being able to really screw with Owl for quite a few months, though.
Seriously, guys, it's shit or get off the pot; if we don't want him here, ALL OF US need to stop responding to him.