I join several airdrops before and it turns out its a fake or scam. I think thats the problem, its difficult to identify real airdrops because most of them are scams.
Because they also have twitter, ICO, Telegram and many more that make them really true in airdrop form. Other airdrop force you to donate in order to get your token from them.
Many people got hacked and scam because of airdrop. Because of bad experiences, do not let in again on it specially those who want a donation before they give the free reward for you after you joined. Airdrop is not being helpful nowadays but give problems and make you not to believe on every projects even has good whitepaper and purpose of development. Keep safe of your account not only account connected on wallet but also those media account that shows your real identity.