You pay nothing to get them, every free money in crypto is called AIRDROP.
Why do you think Airdrop is free money? I don’t really think so because you will have to perform some tasks before you will be able to receive the airdrop, the time and effort spent in performing those tasks is something, so the reward you are getting is not free.
Yes they're Free money and not all airdrop required you to do tasks, Apes NFT holders were airdrop Ape tokens just for hodling pieces of their Nft and there are many more projects/exchanges that airdropped their customers in the past without tasks.