Why do some projects do KYC for bounty? Is this a legal thing or is it a way to make sure they are not being scammed by bounty huntrs? Are there jurisdictions which would require bounty to have KYC? This is not a token sale after all.
Its a good way to eliminate duplicate entries, scammers, etc.. Project team claims this when they go for KYC especially for bounty hunters.
Aside from that, I think projects do use KYC for their future promotions by using their information, to target a demographic and gain more engagements. KYC is such a good way to help a project but for bounty purposes, I don't really think it's needed, when some of them won't even get you a huge value of tokens.