I've just returned from a 2 week cruise. There had to be 2,000 passengers on this ship and almost every one of them had a book. In fact some told me that they had read 4 books during the trip. When I visited the library, the librarian told me she had books moving very fast.
I walked the decks looking at what was being read. Cussler, Ludlum, Paterson, Roberts, Clarke and deMille were the more common authors I saw. There were many I never heard of.
It seems to me that cruise ships were an ideal place to get your books located. It's a growing business.