You didn't quite get what the word 'bounty hunter" meant in that reply, there are two different types of users with signatures on, those who simply wear a signature just for the rewards attached to it, this sort of people would post on a 13th page thread in the altcoin discussion, they would contribute nothing to discussions and spam the forum just to reach maximum posts.
But the other type simply take their signatures as added bonus or incentive for being a member of this great forum, contributing to the growth of the forum, no doubt, with quality posts and replies, they do not take their signatures as a job.
The former was what @actmyname was actually referring to.