Trading need investment and without that, you can't trading! So commonly you can't generate money from trading without investment. Besides bounties and airdrop could be an opportunity cause you don't need to investment there and there is a good chance to and good amount of money if you can find out good project. You shouldn't join every project randomly. Where are you need to have some analysis yourself, gain knowledge about Crypto, Read blog or YouTube videos will help you to analysis and gain more knowledge. I recommend you to rejoin airdrops and bounties again cause I will there will be many upcoming good Projects due to bullish session.
Trading requires money while investing is your choice, because when you invest but don't have money then you can never do it. Bounties and Airdrops are only a small part of getting additional capital, but you have to know that these two methods cannot provide a guarantee of getting money quickly and sometimes what we do is not paid according to the effort we have made.
Trading is also a choice. No one is forced here and in fact many are scared to do it because they always hear scary feed backs about it. Both trading and investing requires money but there must be activities related to them which lets us earn money freely.
A crypto wallet or exchange for example can run a promotion like that, so it's important to stay up to date with them, if we are a budget user. Bounties and airdrops can still be a big thing as long as you are good at finding a high-quality project. If not, then we better try our luck else where on to something that is more guarantee, so that we can't waste time and we can start trading or investing immediately.