People want there to be one choice for buying ebooks, I think, because they're sick of the incompatibility between platforms. I want to be able to buy books from anywhere I want and read them anywhere I want, too. Right now, because the big ebook publishers/retailers are locking down their wares to a single device and platform (a dedicated app per retailer is lock-in, regardless of how many operating systems it runs on), the simplicity of a compatible format is just a dream and the only way to get what we want is to choose one retailer over the others.
The retailers, of course, are all on board with that plan, despite it being terrible for their customers. We as consumers need options. We need competition, and that means compatibility. We need the retailers to stop their monkey-feces-flinging fights, their indiscriminate use of padlocks nobody asked for, and start serving their customers out of necessity. We need them to drop DRM. On everything, right now. The fact that we as consumers, so far, are going along with the DRM lock-in, even defending our chosen retailers, means that we are not understanding the stakes of the game. If Amazon "wins" the ebook publishing "war", everyone loses, including the authors who publish with them and the readers who chose Kindle. And of course everyone else loses, too.
Mokalus of Borg
PS - If you don't stand to personally gain from Amazon being the only winner, you shouldn't defend them.
PPS - And definitely don't fight for them.