Before Christ, there was Yuletide -- no disrespect; the Christian Church was probably quite wise to connect this ancient festival to a celebration of the birth of Jesus. I'm just saying this to point out that the secular aspects of the season, as well as the religious content of non-Christian winter observances, are nothing new and nothing that should make Christians uncomfortable.
Also, they're not the exclusive property of Christians -- evergreens brought indoors, huge extended-family dinners, exchanging of gifts, etc., have no more to do with the birth of Christ than they do with Chanukka, Ramadan, the Winter Solstice, whatever. Well, I suppose these customs might have a bit more to do with the solstice than with anything else, since they date back to a time when the solstice was the only reason for a midwinter celebration.
We should all be able to agree about peace on earth, goodwill towards all, feasting, giftgiving, and hope for the coming spring.
Of course, the most obnoxious instances of commericialism are probably equally offensive to Christians, Jews, Muslims, Buddhists, Hindus, secular humanists, Wiccans, observers of Kwanzaa, Deists, Shintoists, and anyone else I forgot to list.