Agree! If you joined a campaign managed by known bounty managers here and usually they are btc paying campaigns, you are at least safe and your effort will be paid. But if you decided to participate in coin or token paying campaigns, it is your responsibility to do the assessment if they will really pay and if they will really have value in the market. Listing all those scam projects will not have significance if people are continuously joining campaigns. And the fact that they are a lot, it will take so much effort to list all of them for nothing.
The reason I am talking about third party and competent managers because they usually choose projects which have potential and have a good team behind it. They are not careless like others who for just some few bucks choose any scam campaigns to manage. Also since they are experienced, their decisions are not influenced by the team and they do their managing tasks timely and answer any queries what others have.