Don't look here for help - organizing a party to celebrate National Goof Off day probably goes against the theme.
Festivus, a well-celebrated parody, has become a secular holiday celebrated on December 23 that serves as an alternative to participating in the pressures and commercialism of the Christmas season.(Wikipedia)
These food & drink holidays don't always land on a logical date or time of year. This one does!
Santa Claus, Presents, Egg Nog, Family, Giving, Trees, Wrapping Paper, It's A Wonderful Life, Nutcrackers, A Christmas Story....
National Fruit Cake Day celebrated on Dec 27, followed one week later, Jan 3, by National Fruit Cake Toss Day!