Their store? I dunno but a lot of games on their got a upfront payment to only be on that store. If the devs choose to limit themselves to one store, fair enough. But I have a very deep problem with them receiving payment for it. Because suddenly the game isn't "who can attract the most customers/devs via the best platform" but instead "who can pay the devs the most". Doesn't take a rocket scientist to see which of the two leads to better store fronts (case in point: even EA, etc. abandon their store exclusivity regularly because customers refuse to use inferior stores/launchers and want to stay on steam)