I wasn't comparing new books to visiting new cities. I was comparing knowing the ending of a book to knowing where you're going on a trip. If I set out to drive to LA, I know where I'm going to end up, therefore I'm spoiled on the ending, but the trip is still worth taking.
I don't think it's a particularly good analogy. I mean, it works for one kind of adventure, sure, but what about the adventure of sailing in the direction you've never gone before with no idea what cities or people may be in your future path, or how you or your fellow travelers might change during the journey?
They're both worthwhile experiences, but you're comparing apples to oranges.