What Avis can do is allow those people to have the same options Hertz does and offer more cars (since Avis has a fleet of its own), while upselling them conventional rentals when customers need a 2-day car for a weekend getaway.
To the right, a button lets you open the book (you can also accomplish this by simply clicking on the book, naturally), view more info on the title, delete it from your shelf or find similar books -- yet another spot for some e-book upselling.