Op, should I say that your observation is true or I should go further to explain. Naturally, many people do not come here because of the passion for bitcoin. Some came here because of money and I am among those people, but as the time goes on, I recieved some high level information that made me fall in love with the forum. Now, I have passion for bitcoin. This does not mean that I will quit the forum if there's no longer signature campaign. But it means that my activity will reduce, which is what the OP is saying.
This actually reminded me of the comment a newbie made earlier last year regarding something like this too. The newbie said that he was recommended to the forum by a friend who told him he could make money from the forum. I can't remember the username of that member; otherwise, I would have checked on him or her to see if their intention of joining the forum was finally archived or not.
Maybe when we look into the way newbies are coming to forum from the other aspect too, we could see that some are truly coming onboard only for the benefit of bounties, though i may not have to blame them on this because everyone has his own reason for coming, but if we are introducing the forum to a newbie, we should not give them a wrong impression that here is a place of making money when we truly knows that the platform was only created for bitcoin discussions, if we then have the opportunity of getting other benefits from here, we should only take that as an advantage and nothing more.