I think that the poor excuses are in the other side. Adding DRM to files to actively preventing the user to choose in which devices he/she wants to read the file and for how long the content will be available goes against the whole concept of "buying" a book. When I buy a book I expect to be able to open it in ten years in whatever device I'm using, running any OS that I want. That's why we have standard formats. And I also expect that the quality of a book for which I payed 50-90€ for (because that is normally the price range) to have a good quality and at least a table of contents. A few occasions I had to manually add table of contents for books that otherwise would have been unusable to me.