A drum sounds in the chilly Alpine night calling you from your warm bead to climb upon a giant hare. Over snowy hills and icy rivers you ride into the spirit world where an army of shamans from your homeland has gathered to defend next years crop against evil witches. Few benandanti, cunning, shamans, or whatever else you might want to call them ever chose this life, they were compelled to it. Called by the fairies on some dark night or in some lonely place.
Most of us will never experience the spirit world of the shamans, the witches and the cunning at one time people believed the spirit world was all around them. For fairies lived not just in the forest, but also under the thresholds and hearths of their houses, in the fields where they farmed, in the rocks on hills overlooking their village. Often times what we find in folk lore is that the spirit world isn’t a place, its a state of mind. Those who have studied shamans call this state of mind ecstasy. (European Shamanism)
Take Anne Jefferies, for example. As a witch in the 1600s she often entered the fairy realm, or at least her soul did, her body remained behind, just as a shamans body remains when they travel into the spirit world. Anne Jefferies was always a bit of an odd one. She was a young servant girl who was known for doing things that even the boldest boys were afraid to do. Among these things was her seeking out the fairies.
Turning up fern leaves, and looking into the bells of the foxglove to find a fairy, singing all the time. “fairy fairy and fairy bright; Come and be my chosen sprite,”
She never allowed a moonlight night to pass without going down into the valley, and walked against the stream, singing: ‘Moon shines bright, waters run clear, I am here, but where's my fairy dear? (Hunt, 1903)'
At first the fairies ignored her, finally, however, she heard a suppressed laugh and a ruffle under the branches in the garden. When she went to search for the sound she heard a musical laugh and ringing, Suddenly she felt afraid or whoever might be watching her. Finally six handsome little men in green appeared, the grandest of which wore a red feather, and it was this one who spoke to her with a bow.
Ultimately these fairies brought her to the fairy court,
"She was in one of the most beautiful places—temples and palaces of gold and silver. Trees laden with fruits and flowers. Lakes full of gold and silver fish, and the air full of birds of the sweetest song, and the most brilliant colours. Hundreds of ladies and gentlemen were walking about. Hundreds more were idling in the most luxuriant bowers, the fragrance of the flowers oppressing them with a sense of delicious repose. Hundreds were also dancing, or engaged in sports of various kinds. Anne was, however, surprised to find that these happy people were no longer the small people she had previously seen. There was now no more than the difference usually seen in a crowd, between their height and her own. Anne found herself arrayed in the most highly-decorated clothes (Hunt)."
The only unusual aspect to Anne's story is that she sought out her relationship with the fairies, there were many others who were brought into the fairies court, often before the fairy Queen or King. Here they were typically ordered to use their new found powers to help humanity. Other times, as in Russia a girl might stumble out of the woods covered in moss, with the whispers of the forest fairies still in her ears.
Another man in France was taken into the forest by the spirits who ordered him to "rob from the rich to give to the poor." Such an order was common for the fairy queen to give. This is likely the source for the original Robin Hood tale.
In Japan there was a young boy who was taken into the mountains and raised by the tengu and mountain kami for a time before being returned to the humanity in order to help people navigate the changing world.
What's important to understand from such stories is that most witches were chosen by the fairies because they wanted to help humanity. Fairies have built our civilization, indeed at one time each technological advance was attributed to them. We might abuse or misuse their technology, just as a little kid might throw his Legos, but many fairies are not against cities or civilization (though some are).
Perhaps most common of all in fairy tales are those who enter the spirit world in order to help the fairies work. Take, for example, the Russian Tale of "The Girl in the Well" in which a girl falls into fairy land where she is asked to clean up after sheep, feed animals, and do other menial tasks for which she is paid in great wealth. Often times stories of the devil trying to purchase a persons soul are corruptions of stories about a forest or water fairy trying to get a person to become their servant for many fairies had trouble with household choirs, or simply couldn't be bothered with them.
There is another reason for fairies to seek out humans, for "when the fairy tribes under the various kings and queens have a battle, one side manages to have a living man among them, and he by knocking the fairies about turns the battle in case the side he is on is losing."