FD does not really understand the modern definition of the Christmas holiday. For one thing, it starts too early (before Halloween, at least in the drugstore aisles) and then it ends completely abruptly. FD has already received the first of the post-Christmas sales catalogs (prize goes to the Metropolitan Museum of Art), a week before Christmas.
It wasn’t always thus. “Twelfth Night” used to be the end of the Christmas festivities, and parties etc continued throughout the time between December 25th and January 5th. Even in the 19th century, here in the US, newspaper advertisements for holiday gift giving were frequent in the days after Christmas, indicating that there an expectation that people would be continuing the celebration.
Perhaps people who put up their holiday lights on Thanksgiving weekend are exhausted and bored with them a month later, and perhaps if you don’t send out a holiday card before the day itself your good wishes won’t be welcomed. But does it make sense to start the holiday build up so early and then, just when the weather is really bad and the end of the year is bringing all of its regrets over the past and anxieties for the future, shut off the cheer that might accompany a continued Christmas celebration?