People challenge books because of the language and imagery. People can go to deep with there words and make the books others read highly disturbing.
Having that said, I’ve read a book that went too deep with the words and made me feel discussed. Others have read the same book and have said the same thing about it.
The book Flight should not be banned or challenged. Sure it goes into detail on how a horses head gets blown to pieces, and how family’s die. But that’s only to get the image right.