I remember JWs saying that Christmas is like throwing a birthday party for the birthday boy, everyone bringing presents for each other, but not for Jesus, and how sad and left out he would feel on his own birthday.
The sheer amount of emotional manipulation, especially on the poor JW children who have to go through months of this hype at school, is the disgusting bit.
All the daft arguments about whether it was 'commanded' or not, Jesus commanded people to love each other, that's it. The rest was left up to individuals themselves. That's the whole and sole point of being a Jesus follower.
Not lording it over each other, not mastering another's faith.
Jesus never commanded anyone to write down his teachings, or that those teachings should be compiled into a book to bash others over the head with, and control them with.