They are not practicing the religion of Wicca. It's sort of 'Girls just want to have fun' - girls just want to play with magic. This is very common with young women, and probably has been since there have been young women. Some of the practices that are shown in the movie are actually, in that sense, fairly authentic, and I created some reasonable sounding chants. Much, much more interesting than the average Wiccan circle, I might add, where people generally don't levitate or cast balls of lightning around, or have a hundred and fifty million snakes in the room.
Reality tends to be a little tamer.
The highest drama you tend to run into in an average Wiccan circle would be like who gets the last piece of chicken at the feast. Look what happened in Salem with the young girls doing fortune telling. It was the same thing. It all ties in to that, and lighting red candles because you love the boy down the hall. Devin says that a major aspect of the religion of Wicca, one of the things that sets it apart, is the focus on the Goddess, but in the movie the girls have created their own deity, whom they call Manon.