These days I am just assuming it is textures. Textures for graphic quality, that I don't need on my merely full HD screens. Makes me usually not even bother buying, let alone installing such a game. Even 23 GB is still tons. When I compare that with how much fun I can have playing games that focus on gameplay instead of graphics, I would rather safe money, than spending it and having to go through my files and delete things, because I need more space for a game.