I don't understand, too, why there are so many participating airdrops appearing on this forum. They are so happy with the free token that they have little to do, but very little value is given once the quantity is increased and the smaller the rewards. So it is always a good idea to join the IEO, STO, ICO campaigns instead of joining the airdrops.
Airdrop is free and give only few task to get it. Unlike ICO,STO and IEO that you need investment just to have those tokens. There are other way to get tokens for free like bounty but you need to wait a month or even a year before you will get paid.
Many people dont want to wait that long or give so much effort in uncertain money.