There are many good reasons. The first thing that comes to mind is that books smell better than tablets. The second is that they don't need the publisher's perm

There are many good reasons. The first thing that comes to mind is that books smell better than tablets. The second is that they don't need the publisher's permission to lend physical books; they do for digital ones. Really, they have physical books today for all the reasons they had physical books yesterday or a hundred years ago.