How Chromecast cost Amazon my Video Purchases

For years I've been waiting for Amazon to release an instant video app for my mobile device. I have patiently continued to make all my video purchases through Amazon expecting that one day this wish would be fulfilled. However, a few weeks ago I finally decided to get a Chromecast. The decision was driven mainly by the fact that my Roku box still would not allow me to stream HBO Go (via DirectTV). So, I picked up the $35 convenience and suddenly a whole new world opened up and I suddenly realized that if I made my video purchases through Google Play Movies I would also have the option to view them on my mobile tech. With that I have stopped purchasing via Amazon Video and instead will be making all future video purchases through Google Play Video. Sorry Amazon :(