I was thinking in terms of a label for the whole category -- but even so I'd argue against trolls being a subset. It seems to me that an essential part of trolling is receiving feedback that one's postings have had the desired effect. There is, of course, the special sub-category of "drive-by troll", but I consider them to be non-prototypical trolls. To some extent, I'd consider trolls a subset of "entirely social-status negotiation with no significant element of information exchange".