Ok, it's a bit late but next year, on the day before Christmas, go to the supermarket and buy enough food to last you for the next month. Sell a kidney if you have to. And wear a harried, almost scared expression on your face, as if they've decided to stop making food altogether and that eventually, no matter what you do, you and your loved ones are going to starve to death.
Yes, I know that the stores are only closed for one day but believe me. After a few years here, you're going to join in this insanely neurotic "tradition" like the rest of us. Why not get an early start?