Color me confused, they're going to keep 30% for doing what exactly? I get that they keep 30% (or possibly more) of Kindle book money because they provide the Kindle. And they keep 30% of the money for App sales (presumably) because they host the files that users of their app store download. But they're keeping 30% of the money for me paying for in-game currency through them and what does that provide the developer with that they don't already have (besides a way to make 30% less money on their in game transactions)? I get that for the user it's more convenient if you're already buying stuff from Amazon but it seems to really screw developers for no appreciable gain (a loss, in fact).