At least with Rimworld you can pirate the dlcs and add them to the Steam copy with no issues.
That’s what I ended up doing since I’m poor. I saw a comment from the devs on the torrent thread basically saying they’re just glad you’re playing it and to consider buying it if you’re able to in the future. Seeing that pretty much solidified them as great devs to me, and when I actually have some disposable income I’ll end up buying them just because of that.