Too many participants ? I must disagree with you , we are no yet on the mainstream of bounties , ICO's and so on. After we gonna reach this stage , we are gonna see some really awesome bounty programs with a lot of participants in all the bounties.
I also agree that the participants in the campaign of generosity, namely the signature campaign is not so much. Several dozen people join the ICO projects, although the ICO team itself is interested in more participants. They, after all, allocate their tokens to the generosity campaign as a percentage of the total number of tokens produced, and therefore the more participants in the subscription campaign are, the more often their ads will appear. And tokens they vseravno allocate the same number.
If there are a lot of such participants for the participant of the campaign, he may not join such a campaign. So I do not see any problems here.