What you need to do, is engage with people so that you're getting federated content from the instances they are on. It takes time, my strategy was to follow anyone I thought was remotely interesting, and then unfollow people I end up not caring much for until I had a nice curated, populated timeline. It definitely helps to not be on a tiny instance, but it's not necessary to be on big ones like mastodon.social.
If they want to spend any money you them on drugs/alcohol... So what? Like, I can guarantee you that if I had to sleep on the street whatever gets me through my day or helps me sleep does that. Giving homeless people food is kind, but honestly it's very common already and they have other needs. I give them money, because I've almost been there a few points in my life.
What you need to do, is engage with people so that you're getting federated content from the instances they are on. It takes time, my strategy was to follow anyone I thought was remotely interesting, and then unfollow people I end up not caring much for until I had a nice curated, populated timeline. It definitely helps to not be on a tiny instance, but it's not necessary to be on big ones like mastodon.social.