I'm a secular humanist and my wife is Wiccan and we callit Christmas. I agree with what a previous poster said about the days of the week being named for pagan deities. You don't have to worship Thor to call the 5th day Thursday. Also, you don't suppose all the revellers at Mardi Gras are going to Mass in the morning and rubbing ashes on there forehead, do you?
    I do understand some people not wanting to be wished a Merry Christmas. I used to run a phone center in Central Ohio where the main ethnic group was first and second generation Appalachians. I had a really hard time trying to get some of them to not wish strangers a Merry Christmas on the phone. "Merry Christmas, Mrs. Rosenberg" might grate on my ears, but they didn't seem to know better. (Once when I was explaining that we would suspend calling in certain areas during Yom Kippur because of a large Jewish population, I had a young lady ask me in all seriousness, "What are Jewish people?".) I finally convinced them to say "Have a nice holiday" because everyone gets a holiday even if it's just a legal one from work.
    We cook huge feasts for family. Christmas dinner is ALWAYS roast beef and Yorkshire pudding. (Turkey is for Thanksgiving and ham is for sandwiches, Philistines!) This year with French Onion soup using chicken broth instead of the traditional beef broth, super smashed potatoes, glazed carrots, biscuits, fruitcake, and pecan caramel pumpkin pie. This is after cooking a large amount on Christmas Eve when we hosted my wife's family's Christmas party. We'll be eating leftovers till New Years. Then we'll host another party on New Years Eve.