The main difference is that stable versions of the game are published on this page. And for people who support the game financially, early beta versions of the game are available. Also, thanks to some of these people, errors in the code are identified, in which most users do not participate. In addition, those who support the game receive more attention, because thanks to them, in fact, the game continues to develop. Because there is almost nothing free in our world.
Well, the rest of the users receive a ready-made version, here, for free, at the end of beta testing.
And the authors of third-party sites publish beta versions as stable, hence the confusion.