Hello Alisa, bounties are like freelance marketing projects, it's not about the investors you pull in, it's about the traffic you create. So if you show the ico to 1000 people instead of 100, you still create 10 times more traffic and through word of mouth marketing, 1000 people create even more than tenfold traffic compared to 100 people.
But most of the airdrops use a referral system, you get more coins from the airdrop if you refer and make your friends sign-up.
Yeah, I also thought that crypto community must be really... closed, I mean that you will always notice a project that is a lot of talked about, and sometimes it can even become annoying, that's what is happening to TokenGo now. As the task of bounty hunters is just to mention it everywhere, but not to present it in the best light. And same with marine-
fckng-coin, that is being promoted here by a simple spam (actually, I don't think it is a part of their bounty program, but whatever, it's also word of mouth marketing of some kind).
But still I think that referral links work even better, because if a person gets reward for making people really interested in a platform, he works for a certain result, so it is result-oriented management. I can even give you an example: you probably know how many users BountyHive platform has now? It's because it has an affilate program. People are really exited to share their knowledge about bounties even with non-crypto friends.