Chuck's messages are there in the books, you just have to look past gruesome/shocking parts.
For example, soap - obvious symbol for cleaning, but when altered just slightly, can be very destructive, something meant for good, turns out bad, which is why the narrator tried to stop Tyler. There are lots of subtle messages throughout his books.
Haunted - hated the actual story line (all the, "Oh I suffered the worst" shit got really annoying, but I loved the stories.
Rant - A close second to Fight Club for my favorite book. That was a really good book.
Choke - Didn't really like the beginning, but it got better as it went on. Disappointed by the end (I thought he was going to get stoned to death, that would have been a much cooler ending.)
Invisible Monsters - My least favorite, easily. It seemed like he was just trying to hard.
Diary and Survivor - both OK books, not my favorites though.
And that's all that I've read of his, i'm rereading fight club right now, then i'll move on to Lullaby.

I'm torn. As excited as I am to see both Choke and Chuck receiving the credit they deserve, it's posts like these that scare me. I started reading Chuck at 13 and even at that age could have crafted a better argument (much less post) than 90% of the people here. Reading his books throughout the years, I can see a marked change in not only his writing but also his fan base from thoughtful intelligent, progressiveness to commercialized shock factor fluff. Anyone read Snuff?? Granted Chuck has always been amazingly in tune with pop culture and had a gritty sadism that is easily packaged, I guess I had higher expectations of his work. Even still, I continue to read everything he publishes and am anxiously awaiting the release of both Pygmy and Choke.