Do you have any experience to participate in any of the bounty and airdrops? You may have some point to your statement, but not all bounties nowadays are bad, there are still few of them remain good in terms of giving a rewards depending in the bounty manager who manage it. Second, true most bounty campaign are always turned into scam in the end but like what I said, for the bounty hunters for them this is a job anyhow that will give them a profit in the end even they knew there is risk in it.