Fans of The Avengers fans are probably the ones most likely to pirate the movie after a minute's worth of inconvenience.
Meanwhile, Disney can take away a purchased movie from Amazon because the parents probably (a) already have the Disney channel, and (b) are willing to pay for it. https://news.ycombinator.com/item?id=6911944
It's a non-story to the mainstream media. Amazon said it was a temporary issue unrelated to Disney's request to stop selling it. Those who had purchased the movie and lost access had their access restored.
Meanwhile, Disney can take away a purchased movie from Amazon because the parents probably (a) already have the Disney channel, and (b) are willing to pay for it. https://news.ycombinator.com/item?id=6911944