Since trolls don't get banned, and they feed on attention, I just click Ignore. But that's not for everyone: I don't get why people are still posting in self-moderated topics when the warning on top shows all 25 posts have been deleted.
Drive-by sig spammers post without reading the OP, sure as shit they're not gonna read the line above the OP nor do they care as long as the post stays up until the campaign manages does weekly counts.
Rule #1 is #1 most abused and #1 least enforced.