My daughter watched a clerk brought to tears by a customer after wishing them "Happy Holidays." How pathetic and contrary to the spirit that she was trying to foster.
I went to Catholic school all through grade 12 and we were always forced to wear buttons/pins/sweatshirts that read "Jesus is the reason for the season", and the nuns actively told us to argue with anyone who doubted or believed otherwise. In college, when I was a RA and put up a holiday board discussing the history and traditions of Christmas, Hanukkah, Kwanzaa and Ramadan, I was reprimanded for including the latter half and semi-frowned upon for putting up the second holiday.
Hell, even looking at the Facebook update for Chick-Fil-A yesterday when they mentioned the word "holiday", commenters were getting livid and threatening to boycott (I guess the Summer of Love is but a distant memory).
I say "Merry Christmas and Happy Holidays" - a split second longer but all encompassing