I used to live abroad and bought many books and also E-books. I had to leave all the books behind.
My nook allows me to read in bed at night, when others don't want the light.
There are books which may not be available in your local store, but you can download them from anywhere in the world. Being addicted to books, that's a big plus for me.
Last but not the least, I can carry my entire library wherever I go.