Over at Mental Floss, Jake Rossen explains why books often have blank pages in them. It has to do with how many pages the text of the book takes up and the fact that "signatures," or the groups of pages combined to make the book -- need to be divisible by four. If the page count of the book divides evenly by four, then no blank pages are necessary.
But if it's an odd number, then the publisher either sends it out with some clean white pages or finds something else to print on them. Sometimes it's a list of previous works, or publishers may tease another recently-released book like the one you have in your hands.
However, Rossen does not deal with the question of books that should probably have even more blank pages than they do, say, cover to cover. Like any of these. A bunch of these would probably be more useful that way. And of course these.