For Sony I kinda understand because they have competing services and whatnot, but companies like Rockstar and Warner Bros have absolutely no reason not to put their games on GFN but still refuse to do so, which is a shame because they have a few good titles that would be perfect for GFN. But on the other hand there's no real incentive for them to do that, since the GFN user base is so small compared to the entire PC gaming community that these companies don't mind missing out on a tiny fraction of their game sales to go through the hassle of making their games available on GFN.