This is not something that can make person rich, except for some faucet owners/related services - but for some people this is good start to get some coins if they have no other way to do that.
I understand that fact, with specific amount of coins/ tokens/ btc airdropped or paid via campaigns, bounties, faucets, its meanings are totally different from nations to nations, from locals to locals.
So, it is too general and incorrect to draw a general statement here.
For instance, the airdrops on blockchain.info, that gives $25 for each qualified case via Stellar means a lots for things for locals in those nations you mentioned, especially in Venezuela.
But, the cost for airdrop hunters is they have to do KYCs.
People in rich nations, or people who have some BTC, 10, 50, or more will never join this.