No any difficult task and we can earn free money that why so many person join the airdrop. But these days so many campaign scam and few campaign is good..bounty is better than airdrop but so many task we have to complete during the campaign
It is not safe to participate in most airdrops running actually, and even if the airdrop is legitimate, don't expect a high profit, because the payment rate is very low. It is sure that bounty is better, but not any bounty, only the campaigns linked to the promising projects that have the potential to succeed.