Including "The Lottery" in the curriculum, introduces an enormously rich tradition to the classroom, reinforcing larger themes in American literature. Jackson draws from the American horror/Gothic tradition made popular by Poe. Her work serves as a link between the elder statesman of gloom and doom to the best horror writers of today, such as Stephen King and Anne Rice.
There's no doubt horrific tales are a major part of popular culture. We're willing to go out a limb and say that "The Lottery" probably has a bit more literary merit than a lot the genre's modern incarnations. The story provides a great opportunity to reel students in with a genre they recognize, and then to show them how that genre can connect with larger ideas and themes.