I wouldn't make such an accent on bounty campaigns. Spammers create problems even when they don't wear any signatures. Not everything and everyone here on the forum care s much about signature campaigns, actually. Of course, the later could provoke more spam and shit content, however, in my opinion 1miau didn't mean that bounties are the main problem and the key reason why he created this thread. It is more about conscious behaviour here on bitcointalk and preventing deeds that destroy forum and its community step by step.