They have no interest in knowing anything about Bitcoin. I don't understand why they do that. So do they lack knowledge about this forum?
Like you've said they don't have any interest. It's not that they lack knowledge but they are more concern on ways on how to do or earn money here.
People who do bounties are generally from third world countries and they are obviously not financially independent.
They will realized this in the end. Also came from this and able to stop myself from doing social bounty and divert it into something more worth it. Those 95% assumption by OP is technically reduced somehow in the long run. Some of those are probably changing as they observed what is best here and that is not on spamming on bounty.