I believe that there are other reasons and benefits to Christmas other than Jesus. Yes, Jesus' birth is what is being honored on Christmas. Quite a few people do this because they are thankful that Jesus sacrificed his life for us. Others (myself included) believe that Jesus merely died trying to set us free from Jehovah, and that is enough to honor Jesus (and Satan, who is the other being that tried to free us from Jehovah's tyranny).
Christmas is also a day to enjoy one's material blessings. That is why we have gift giving, and people generally get the day off to enjoy their stuff. Traditionally, people give gifts because they want others to be able to share in this blessing, and in response to receiving gifts.
We also see this as a time to enjoy the lights (most people, myself included, enjoy colored lights), colors (red, green, silver, and gold go very nicely together), and shapes. A well decorated Christmas tree has the right balance of lights (clear and/or colored), sparkle, simple ornaments, intricate ornaments, and variety that most people enjoy. Even a poorly decorated tree can teach people to do better, and since decorating for Christmas is an art, it helps one to appreciate art that much more.
Christmas is also a time to enjoy family and friends, to reflect on peace, relax, enjoy fine food and drink (never drinking and driving--there is no proper time to drink and drive), enjoy the snow (instead of swearing and cursing at it), and is a transition to a new year when you have a chance to work on some aspect of your life that needs work. I think most of us can find at least one of thsee articles to enjoy, and that is sufficient reason to celebrate Christmas even if you don't like the other aspects.
And, for those who were Jehovah's Witlesses, celebrating Christmas has one more dimension. It serves as a slap in the face to those witlesses that would be trying to get you to continue wasting your life in their religion. Children also get the dimension of the excitement that leads to the big day--I think most small children that are brought up around Christmas look forward to it (and they wish every day was Christmas). Adults get the chance to enjoy it, returning themselves to childhood for the day.