Nowadays many people think this forum is a source of income, I don't know why they think like this. This is forum to discuss about bitcoin, not for work! If you want to get money, focus on 1 skills what you good or like... And apply on freelance site. Actually you can earn more money by that's job.
Bounty campaign is not worth it, only wasting your time with worthless coins, avoid it.
Keep in mind, signature campaign is only a bonus from your dedication to forum... similar like people give merit (bonus) on a high quality post.
Because there's really a income generated from this forum if you are skilled and knows on what you are doing to provide a quality service or have goods to be offered on your clients.
And I agree with you about those sig campaigns earnings since this is temporarily privilege for users who active here and people should not think that they can earn with this forever since ther are times that campaigns stops and I'm sure people don't want to get broke since finding a good campaign is so hard these days due to competition here.