I don't celebrate Christmas because it is the fictional birthday of a [most likely] fictional person who represents a fairy tale that modern day people embrace in all of their ignorance. I celebrate Christmas because it is the one time a year when most people make an attempt to be somewhat decent to each other*. I wish that were the case the other 364 days, but it isn't. So you take the little victories where you can get them.
*I also like "Christmas Vacation" with Chevy Chase.