A lot of depends from the project. Now gaming NFT projects attract a lot of attention and their airdrops are very popular. Just see the results of this airdrop
https://twitter.com/spacegrime/status/1396545308809601025 and you can see how popular gaming airdrops and how many users they have.
The popularity of CryptoKitties attracted a lot of gamers to the cryptocurrency. NFT are so popular in gaming industry because they allow not only spend money but also earn money too.
CryptoKitties was very popular, becaused they allowed to earn a lot of money on buying and selling NFT tokens. One of the virtual cats of CryptoKitties was sold at auction for $140,000 on May 12, 2018. That is why NFT games now so popular and a lot of people participate in airdrops of NFT games.
Now NFT are given on airdrops to attract attention of the cryptocommunity to the project. But the price of NFT depends on the demand in it and how many users want to buy NFT. It must be competition between buyers who want to buy NFT.