Because the films are always crap compared to the book, always leave something out, and just generally are never completely true to the story? I'm awfully defensive when it comes down to someone putting me in the right position so this would have been my response.
I work for Post Production in Fox. I can tell you that they HAVE to leave stuff out. Even some of the best adaptions, Game of Thrones, Lord of the Rings, and others, still leave stuff out. My complaint is when they add stuff in.
I freakin' love books! They let you imagine the story in your head the way you picture it, but when it comes to the movie and it's completely different than to what you saw in your mind, it makes it a bit less enjoyable to watch.
Reading lets me create the scenes and picture the characters in my own way based on what they describe in the book :)
If there is a book I really want to read and a movie for it is already out, I always watch the movie first. That way I'm not let down, I'm pleasantly surprised by how awesome the book is.
Books put you in another persons reality what they think, see, feel and touch books are like an opening to another dimension, another world. Books are more important than people may think but the day they areally gone (I hope not ) people will finally realize what an important role books play
Reading lets me create the scenes and picture the characters in my own way based on what they describe in the book :)