Even without data caps, a TV connected box shouldn't be pulling down hundreds of GB per month while idle. Without data caps the author of this post may not have had an issue, but that still doesn't make what Amazon's doing OK.
Amazon is doing exactly what they should be doing. Especially if their box is doing the right thing and downloading the shows in the middle of the night. Comcast et al should be thanking them for this because it moves a huge amount of traffic from peak to off peak and reduces the amount of capacity upgrades they'll need. This is a prime example of why data caps are stupid.
At least Amazon should be offering a setting to disable that feature, and whenever someone want to play a movie and the setting is off, then warn the user that he can always turn it back on...
At least in the USA where bandwidth is still limited Amazon should be offering the proper setting for the user to decide. [edit: fixing typo]
1. Pre-cache TV show A
2. Local store full
3. Delete TV show A
4. Pre-cache TV show B
etc