I'd like to believe this, but then I can't buy an Apple TV through Amazon because of some petty dispute over Prime Video (which I really don't care about). So if Amazon the store can pull products to try to protect prime video, then how can I be sure that other units won't?
Well, they claimed they removed non-Amazon devices because they didn't support Prime Video. However, for stuff like Chromecast, the burden lies on the app developer (which would be Amazon) to implement Google's Cast SDKs to provide support.
Because of this, Amazon cannot distribute Google Play Services on their own Android devices and therefor cannot use their own Android devices to cast to a Chromecast. They could enable Prime Video on other Android devices but not their own. They feel this will cause confusion and therefor have decided not to write a Prime Video app for Chromecast. Saying "oh, Amazon just doesn't want to write a Prime Video app for Chromecast", while true, doesn't truly explain the complexities of the situation.
The business decision to remove Chromecasts from the network steps from the above desire to prevent confusion. I personally don't agree with it but I understand it.
