My proposition is that the typical fare for a book club discussion is virtually precluded by the nature of the work. The lack of depth and character development, coupled with the absurdity of the plot, make the standard analysis of characters and motives, ideas and emotions, virtually meaningless.

However, by virtue of the fact that the book is lacking that, and yet is considered a "classic" in many circles (though not without a heavy dose of academic criticism, as we see from what Eco and others have had to say), we are discussing literary methods generally.

When all is said, perhaps that has led to an even better discussion than I had hoped for, though certainly the nature of the discussion will preclude the tea-and-crumpets introductory party for sci-fi/fantasy geeks you had envisioned. On the other hand, isn't arguing over what a "good book" is at the heart of most of our discussions?