This is something I've been thinking about for a while. Sir Gawain and the Green Knight is probably the book that began the fantasy genre, so let's look back to that. I don't think many readers would consider it suitable for children, since the story has heads rolling and main characters walking into apparent death. One of the greatest fantasy epics of modern times, The Lord of the Rings, features terrifying monsters and enormous numbers of deaths, again not very child-friendly. Its central themes of friendship among men and bravery don't seem to be aimed at children, either. The Star Wars movies (which I hope we're all familiar with ) were criticized when they were released as being too upsetting for children, with references to scenes such as Obi-Wan's chopping Ponda Baba's arm given frequently. Most recently, the Harry Potter books, which started out being aimed at children but eventually morphed into adults' books when the author realized they would sell no matter what audience she targeted, have embraced heavy Satanic symbolism in descriptions of the practices of the dark wizard Voldemort and his followers, meaningless deaths (including one of a teenage boy), and many sex/genital jokes and references (I think there were about half a dozen in Goblet of Fire). What I'm leading up to is this: Why is fantasy considered a children's genre, if the books written in it have been meant for adults from the inception of the genre right up to the present day? Do many adults falsely assume that only children are imaginative enough to appreciate the books? Is it the writers' and publishers' mistake because they market the books incorrectly? Have fun.