My guess is that it was children who began this folkloric game of telephone, because it's almost always the children. They hear a story, it begins to morph, they grow up, they repeat the story to their children, perhaps with a little spice added, and on it goes. Because children, then as now, seem to like to make any urban legend as gruesome as possible and one-up their friends, eventually we end up with a Christmas-themed scarecrow that eats kids.