What's With All the Blank Pages and White Space?

I can't believe the number of times that I have looked at a print book preview and seen not one sentence that shows me the author's range and style. Could this be a deliberate ploy on the part of the author to shield his work from the inquisitive (read potential book buyer) eye?

Print-on-demand books are expensive enough, without stuff like this. Do authors really think that people want to pay for white space and blank pages? Yes, a beautifully formatted book is a joy to behold but these books are printed by the thousand and are thus much cheaper than any print-on-demand- book can ever be.