That was my thought. They already give away free games over Prime, if they leverage that they have already given a large number of people stake in their new market place. Plus they own Twitch, I don't believe there is a publisher who isn't interested in the idea of people being able to impulse buy whatever there favorite streamer is playing without even leaving the stream. The strategy is pretty easy actually, give streamers a cut of each sale and encourage them to put up notifications when it happens like they do subs and cheers.