Happy Holidays vs Merry XMAS

This time of year brings with it good cheer and wonderful spirit BUT on the other hand it also brings a lot of frustration and aggrevation. Yes going to the mall and looking for parking during December can be slightly hellish but these aren't the annoyances that cause me the most stress.
What really peeves me during this time of year is the general assumption that everyone celebrates Christmas and that there is a lack of sensitivity to those who celebrate other religous festivals. How many times am I forced to smile politely when a client says Merry Xmas or a co-worker asks me if I've done all my shopping..I understand they are just trying to be polite or show interest but with all the "mutli-culturalism" in our society these days one would think it would be easier to understand the need to recognize that not everyone celebrates Christmas.
I am not trying to be a grinch nor am I saying that we should now call a Christmas tree a Holiday tree but on the other hand it would be nice if all facets of our society here in Canada were recognized during this time of year or always for that matter.
It is quite frustrating when I am laughed at at work because of a request to call our "christmas" lunch a holiday celebration due to the fact that that there are so many people of various cultures in our office. When will people learn that some people are different and we would appriciate a little recognition or just know that an effort is being made to understand OUR holidays and tradionts.