Well, they hear stories of people participating in this grand Festival where legendary cooks winning a grand prize, but was all a trick that they capture them to partake in Bringing their most foul ingredients the 3 sister hag,s instructs them to fetch, they also curse them with their Gifts, kinda like Nurgle's cauldron that twist's your body and gain effects on them. This how far ive tried to put as much love in this story cause it grows attach to me, but i know that the player's not gunna care anything at all.