Does it really matter though?? Maybe some people don't want to fuddle around with a device all day. I mean think about it. Except for the space an ereader may save you from storing books, is it really more practical in the long run?
Look at all the hours readers waste here talking about their ereaders, fooling around with the files and fonts, losing books, complaining about prices, worrying about the fact if they own the book or not, batteries dying, dropping and breaking the device, getting addicted to buying multiple readers, etc. etc.
Can anyone really blame or be surprised that a good majority still do not want an ereader.
A paper book you go out and buy sit down and read. That's it.
Now I like ereaders but I can most definitely see why some people would not want to deal with the hassles that come with it or the obsessions over minutia that can result with owning one.