I think it's the computers. Most of the ghosts I see weren't trolls, just young accounts going far enough against the grain to get downvotes. If it's humans doing it, they are absurdly harsh.
That certainly fits the bill for PhantomLobe. Her/his second comment wasn't flamebait or spam, more just an slang laden "me too" style comment. With no karma the account submerged and now PhantomLobe is commenting into the ether with no one listening. I just can't stand to see people was their time like that (unless they are trolls/spammers).
