Not all steam games have DRM

This is true but you don't know ahead of time before you buy a game, you have to gamble on it being the case or not (i've found that while some lists exist in places like pcgamingwiki, they tend to be both very incomplete and often wrong).

Usually indie games tend to be DRM-free though, so if an indie game isn't available on GOG or Zoom Platform (another DRM-free store), i end up buying on Steam.