Again as Notjohn suggests, when I look at my own reviewing habits, I find that every book I have ever reviewed was a book I had bought as a print edition (often bought used from a local bookstore, so rarely does it say I am a verified buyer.) I own more than 10,000 books, not including an additional 7,000 comic books, and 400 cookbooks, nor does this include the previously mentioned 5,000 ebooks do