Here's why:
* St. Nicholas Day: The Dutch celebrate St. Nicholas Day (Sinterklaas) on December 5th, where children leave their shoes by the fireplace for St. Nicholas to fill with treats. This happens *before* Christmas.
* Christmas Eve: On Christmas Eve, some Dutch families might hang stockings (or "Christmas socks") by the fireplace for the "Christmas Man" (sometimes called "Santa Claus") to fill with gifts.
So, it's more accurate to say Dutch children hung shoes by the fireside for St. Nicholas, and then stockings for Christmas.
Is there anything else you'd like to know about Dutch Christmas traditions?