Christmas doesn’t exist in the Dishonored universe? Well it does now. At least in some form. After all it’s the best occasion to exchange presents. And since most whalers probably do not even remember their birthdays, it will be a welcome cnage.
So have some happy whalers who are preparing to have some festivities!
(Plus during the darkness of winter, it is likely that people would like some light and decorated things around them. No sun can be frustrating, so make the best out of it by celebrating)