Moreover guys, there are cases with old releases when even if the game is the same, the gaming platform does not offer the same stuff INSIDE the game (and I am mostly talking about languages). As an example, at GOG.com you will find PoP The Two Thrones in 3 languages, while with Steam (here in Europe) or Uplay do offer 5 of them.
Anyway, we are not talking here only about retailers. We are talking about real gaming platforms with an specific app for installing in you system, platfoms with their own servers for online multiplayer gaming.
I'm not talking about places for buying keys, but when we recognize Steam and GOG as individuals for PC gaming, we should give the step to give its place for Origin and UPlay already.
I cannot give any opinion about others, but I'm quite sure about these two! O.o