I don’t know exactly why, but that lump of coal in your stocking used to terrify me as a kid:
“Omigosh! I used a swear word! Is he listening?!”
“Goodness no! I forgot to feed the cats! Santa, I’m sorry!”
“AUUUGGHHH!!! I stole a piece of fruitcake! Why?! I don’t even like fruitcake!”
Nowadays I don’t worry so much, but still, it makes for a fun cartoon.