Additionally, I'm pretty sure one of the conditions is also to make the Play Store the primary (if not only) preinstalled source of apps for the device. This conflicts with Amazon's own app store, which is integrated into the Amazon app (as distributed by Amazon; the one on the Play Store omits this feature).
Hell, the whole Play Store is basically a direct competitor to Amazon's multimedia offerings. While Amazon's own behavior is scummy, it's also unsurprising given the situation.
Hell, the whole Play Store is basically a direct competitor to Amazon's multimedia offerings. While Amazon's own behavior is scummy, it's also unsurprising given the situation.