If celebs at a resort are buying books on the spot to hold outside at the beach, it is to be seen with a book, not to actually read said book.
Either way the sale is made.
That was an element in The Great Gatsby. All the books in his library had pages that were not cut. (When a book is made multiple pages are printed on a giant page, folded, glued in place and then the sides are cut so the folds open up)