I have bought games for 1-3€ on allkeyshop a few times, you’ll get a steam gift or key for the full game for your steam library. Obviously they’re from shady sources. Maybe it’s mostly a trick with regional pricing or something like that though? So some of the money goes to the devs?

I like it because I get updates, automatic steam Linux support and everything, but piracy is good for games just to try them out. Of course buying for full price also is a good option.