In the yuletide season, I wish everyone I meet a jolly "Happy Christmas!" Some do not take kindly to this greeting, and protest, "I don't observe Christmas!" If you do not observe Christmas, that is your choice, but these people act as if I'm trying to offend them. I wouldn't be offended if a Muslim wished me a happy Eid al-Adha, for example, I know they're just trying to be friendly.
So, to those who go beyond simply not observing Christmas, to being anti-Christmas, I respond to them saying, "Do you want to have an un-merry Christmas? May you be devoured by a horde of wild boars on December 25!" This shuts them up quickly, when I wave my totemic staff and they discover that I am the High Shaman of the UMBC Wild Boar Cult.