Micah made this here statement on Twitter the other day, articulating neatly what a lot of us have been thinking for a while now:
It is not random that Amazon does not use EPUB. Consumers dislike DRM, but are all right with proprietary formats. -- Micah (@micahsb) [August 17, 2013](https://twitter.com/micahsb/statuses/368546780943642624) Very true.
It’s something that has bothered me for years and years. I spent years arguing against the use of proprietary formats in interactive media academia (they were unnaturally fond of what was then Macromedia Director).