I agree with you on a philosophical level, as there's no need for KYC for legal compliance. However the reality is this: People on this forum and elsewhere have hundreds, sometimes thousands of accounts registered. Some of these people have offices with hired workers that do this for them, others use bots. The reality for most airdrops is that they are centralized to just a few people with thousands of accounts. Without KYC the airdrop is not fairly distributed, and these scammers get most of the tokens. So in essence KYC is a way of countering this.
The solution of KYC isn't ideal, but what better system could you propose to alleviate the above issue?
Simple. Don't airdrop large proportions of the coin supply.
Marketing strategies, the more people seen in a group chat the better. They would airdrop millions of coins for their community to grow, and giving them their start up coin loses them nothing.
People are blind folded and investing in ICO now a days that have many supporters, they trust and invest in it. I am not saying all but some people dig deep and see if the project is worth investing for.
This issue is bugging me as I have KYCed for Polymath (for airdrop), I already regretted things and did not think carefully before the latter happens.