Yobit holds a huge number of airdrops for all the listed coins on the exchange but as you said the amount is always pretty low. actually there is nothing to loose by participating in those airdrops as they are already listed so you can sell your tokens and Yobit is also not asking for some fees or any other thing. I don't like those airdrops which asks for the user to send some transaction fees to the ethereum address as chances of getting scammed are pretty high and also there isn't any assurance that you will make some money on your invested time and money that you spent.
Yobit always provides airdrops with a very large number of tokens like YODA and DICE yesterday, but on the other hand they only become worthless tokens after entering into an exchange, it is free of charge but our work is more valuable than working on useless airdrops.