Well... Interesting concept they've got o.0
http://www.techdirt.com/blog/casestudies/articles/20120221/14301917832/vending-machine-sells-books-whatever-price-you-want.shtml
http://www.techdirt.com/blog/casestudies/articles/20120221/14301917832/vending-machine-sells-books-whatever-price-you-want.shtml