You've been reading at least since the third grade. Unfortunately, too often many of us continue to read at that level.
Let's take "The Great Gatsby" for example. Have you compared and contrasted the attitudes of the mid-westerners to those from the East Coast? Who is the "wild wag of an oculist" overlooking the garbage dump and what does he represent? And who is the "great" Gatsby, who is introduced almost as though he were a circus performer? Does the theme portray Gatsby as an idealist or just another crooked businessman? What about Daisy and Tom Buchanan? What attracts them to each other? What is Fitzgerald's opinion of his characters, particularly Gatsby? Does Nick speak for Fitzgerald?
The Wilsons seem to represent those who have lost whatever strength and conviction they once possessed. How important are they to the plot and theme?
Once you can thoroughly analyze a book like the Great Gatsby, knowing the plot seems unimportant. Books offer us so much more!