Guys, I will tell you something essential in your life:
There Ain't No Such Thing as a Free Lunch!So when an airdrop seems free, it doesn't. It must have costs associated with it, i.e., your identity in the form of email address, ETH address, phone number, ID card, etc. These data aren't free! Furthermore, you risk your ID sold in the black market.
This is sadly the price we pay for globalization and its interactions. Frankly, it also entangles us with KYC validation for ICOs. It isn't just an airdrop problem alone. For me, I try not to partake in airdrops asking for more than the ETH address and email. Those are the only two I can afford to expose. Any additions, I am out.