Christmas is a holiday. Initially it was meant to celebrate the birth of Jesus Christ but it lost all its holy elements overtime. Its just a day that our society picked to hold his birthday on since we really don't know what day he was born on. Then there is the whole Santa Claus thing that sprung up. Santa plays a huge part in a family's christmas than it appears. There is more media promoting of Santa than there is of Jesus these days. Also more people are starting to cross out the Christ in Christmas and using X-mas instead. It may be easier to shorten the word but that also takes away the religious meaning of the word.
In short, Christmas is no longer religious to the masses. Its just another holiday that comes and goes. There is no meaning to it to most people.