If it’s to manipulate good behavior out of your kids, wouldn’t just telling them directly that you won’t buy them the presents they want be more effective?
If it’s to instill the spirit of giving to your children, why not tell them the true story about Saint Nicholas?
If it’s about instilling some sense of wonder about the world, why not teach them about real wonders of the world, like dinosaurs, volcanoes, aurora borealis, the depths of the oceans or the vast expanse of space, etc?