I think the implementation of said DRM has much more to do with it then the actual DRM.
My steam library has 208 games. It's easy, it's cheap, it's quick, and it never caused problems.
Our (shared with my girlfriend) e-reader has no bought e-books anymore. Why?
First off, it's expensive. My girlfriend goes trough about 2 books a week, as ebooks costs just as much as a paperback, that's about 20 euro a week. For some digital copies of something that gives a few hours of medium entertainment. (These are not top notch books, it's easy to read stuff)
It's also clumsy, buying a book is more effort then torrenting it. You still need to transfer it, you have different DRM schemes to deal with.
Our local library does offer an assortment of ebooks for rent. Great idea, horrible implementation, as it requires tons of effort to use. Seach->select->download->load in different application->store it there in a library->convert->transfer resulting file->hope everything went properly->have your PC invaded by the application that manages the rental library. (From Sony, no surprises there)
Reports every once in a while that ebooks go "poof".
Compare that to steam, where I can buy in 2 clicks, I get to use the game everywhere, with easy downloads and no hassle. (And recently, even easy refunds if the game fails to work)