They don't want people reading the "wrong" books. Book burning is fine with them.
Amazing how removing age-inappropriate material from school libraries is censorship, but removing opinions that dissent from the hive-mind on social media either "for the common good" or "perfectly ok cause it's a private company". Also, book burnings by "conservatives" are few and far between, and to my knowledge and observations, consistently condemned by the vast majority of conservatives without quotation marks. Personally, I read and listen to plenty of material I don't agree with, sometimes because it's entertaining and thought provoking (Transmetropolitan, comic book by warren ellis and George Carlin are both getting good amounts of rotation right now for both those reasons) or because I want to see if the opposing views have any actual, verifiable points (Lies My Teacher Told Me is slowly being worked on for this reason)