It could be $X.00 for a book with no advertising. $X.00 -$ Y.00 for books with no advertising. If the advertising were in the form of a column on recto page of Smart QR, what reader wouldn't choose free? If the Smart QR and TinyPurls deliver clickstreams for customer informatics, which marketer wouldn't pay for it.
If this sounds nuts, consider
the recent Amazon patent and the fact that the person who wrote that patent jumped to Google. Then consider that Amazon is now in the Print on Demand book business with both feet. To me, the idea that Amazon wants to get into the printing business with the present business model, sounds nuts.
Free-to-the-user print, means lots and lots of clicks for everyone. That's why my IRA is a collection of printing and newspaper public companies. Publishers? not so much.