Airdrops were so popular among the crypto-community over the years. One of the key features of the airdrops is, it gives every participant a chance to get some free tokens by completing few tasks. Most importantly it is totally free of charge. But nowadays we frequently see a trend where the organizers of some of the airdrops ask to send a small fee prior to sending the tokens. In some cases, they put a condition saying that in order to withdraw tokens or any fund received from the sale of tokens, it is mandatory to take part in their ICOs. I would rather call such events as "Scam-drops" as they not only dilute the meaning of airdrops, but also make people to move away from future events due to lack of trust.
In airdrops nowadays, according to my experience back then which might still happen these days, either you get the token you were promised at, get nothing and the thread of the airdrop disappears cause of newbie manager, or the worst, try to get baited from phishing site. While I am not stupid to fall for those fake My Ether Wallet sites, I wonder how many people suddenly lost their tokens from those though.