I don't wish people a merry Christmas unless they wish me one, and when they do I respond, "And you too." or "You have a merry Christmas too." It's not that I worry about people being of different cultures or even averse to Christmas, it's just not something I feel the need to do. I don't wish people "Happy Thanksgiving" and I have always thought that "Happy Easter" was inappropriate.
I try to avoid shaking hands with people, friends or strangers. It's an anachronism, and I usually want to wipe my hand before and wash it afterward. I don't like to share elevators. I wish grocery clerks who have colds would stay home, and I support mandatory paid sick days from employers.
I have all I can do to put up with the people I love, the affection of strangers holds no interest or fascination for me.
Watching the fight play out between them is like that really old black and white movie, "All About Eve", where the aging star is being stabbed in the back by the overly ambitious understudy. O'Reilly...