Thanks for your work. Now I can distinguish scams on my own. But I'm wondering why there are some campaigns which have only an airdrop?
There are many projects which have the idea that airdropping the coins will make them more popular than running an ICO. So people stock up on ethereum and get a bunch of tokens for the amount of ethereum in wallets multiplied by some factor. Some people even call the bounty distributions as airdrops, though this is not technically correct.
In any case if a project is having an airdropped coin, carefully check what the airdrop is for? Is it to make the coin look popular or is it simple distribution for some harvesting of emails/personal info - these two cases are shady and not very legitimate to me.
If the distribution is based on ether in the wallet multiplied by some factor - then its still legit but its difficult to determine if its going to be a shitcoin in future or not.