In at least the UK, December 26th is known as Boxing Day. This has nothing to do with the sport of fisticuffs. It was originally the day the servants of the Great Houses got their bonuses/ holiday time. I am guessing that’s when buffets came into fashion…the cook would have to leave something for the masters of the homes, most of whom couldn’t cook. Probably came back to a mountain of dirty dishes on the 27th, too. Unless, of course, a skeleton crew remained on duty on the 26th.