Like many other people I'm dismayed at the way Christmas is always such a commercial enterprise in every respect — if for no other reason than the way it is pushed (and pushed, and pushed) on us as an excuse to spend money. Nobody over the age of twelve is going to find this a revelation. But what's most dismaying to me is how it's confined all to the end of the year, confined to a very specific ritual, etc. It's something we can find an excuse to compartmentalize.
That said, I can think of at least one counter-argument to why any particular sentiment, like Christmas or Thanksgiving, gets packaged up in this fashion — it's sort of an adjunct to why, for instance, we shake hands or use certain utensils at the dinner table. It's a broadly-acceptable way to take these feelings, which can be expressed in a way that makes people uncomfortable ("I love you, man!!"), and give them a sanctioned space to be expressed, even if there's a little overkill involved. It's a way to take these things and give them a built-in context for their expression, which I guess isn't a bad thing.
So maybe Christmas is worth keeping for a bunch of reasons. It's a sanctioned space to give something back to life. I just feel that it's okay to give back the other 364 days of the year, too.