It is unfortunate that there does not seem to be a great deal of research on the subject of fairy cults. They varied somewhat from region to region, and this is why it can be difficult to provide a clear definition of them.
Fairy cults appear to have predominated in central Europe, stretching from modern-day Estonia down to the southern island of Sicily. Both men and women were participants in these nightly rituals. Cults today carry a negative, dark connotation. However, those that participated in them in the sixteenth and seventeenth centuries did so either for adventure or in order to protect others from evil.
For the most part, fairies did not see themselves as completely outside of Christianity. Often, they fought against mischievous witches and it is for this reason that they can be considered "Supernatural Helpers".
If a more sinister theme existed, it did so largely in the minds of those who put the fairies on trial. These inquisitors often attempted to stipulate that the fairies were really witches participating in diabolic rituals. Fortunately, fairies were rarely severely persecuted due to the fact that they were not usually taken seriously. If an individual fairy was put to trial and deemed guilty, punishment was usually banishment or a light prison sentence.
In certain regions, fairy cult participants were mainly women, while in others, men predominated. In order to give better insight into the world of the fairies, I will give two specific examples: the female fairy cults of Sicily and the male fairy cults of the Friuli.
Behringer, Wolfgang, "Witchcraft Studies in Austria, Germany and Switzerland", Witchcraft in Early Modern Europe: Studies in Cultures and Belief, Barry, Jonathan, Marianne Hester and Gareth Roberts (ed.), Cambridge University Press, Cambridge, 1996.