If they charge for airdrop then it is a scam airdrop campaign. While there are some airdrop campaigns that actually payout after sending a fee, it's still a risk. They can be trusted if the project is popular and good. It is better to avoid such airdrops.
why take risks with tokens/coins that will be "shitcoin/token". I have never participated in Airdrop since 2018, everything will just be a collection that contaminates the wallet, some pay but the value is much smaller than the exchange fee. it's better to just avoid all forms of airdrops that ask for fees from potential coin recipients..
Look I don't hate airdrops as much as I hate the fake ICOs because airdrops are giving you free coins and one should have no regrets and complaints with something they got for free. Yes you have every right to be upset and make better choices next time but at the end you are getting them for free and if even 9/10 are scams you still got something from that 1 legit airdrop.
The ICOs is where the market becomes worst because they take away money from investors and do nothing apart from fake promises of the price to the moon. I stopped investing in almost all ICOs after being fooled by a few and now I only invest in coins which are listed on decent exchanges at least.