For the people who thought the book was about a tiger in a boat, it wouldn't matter what they read.
Maybe so. What about a 10 year old who isn't aware that books can be taken at more than face value because he's never read a good one? If he is funneled into young adult dystopia land, he may never realize that. Maybe those are the adults (I assume) you've seen across the table at the book club.
Not everyone is going to read Great Expectations and walk away changed. But everyone should be given the chance.