Participated in more than 50 airdrops, it came about 20 dollars for half a year. So I don't know if it's worth to spend more time for this. Although some airdrops gave more money than the bounty campaigns
Still worth in sometimes having receiving airdrops because its simple task to be work on going to make earn not so big but can valuable in a future. and of coures its definitely profitable soon as the value of market will increases.