Mathew, I would urge you to go back and reread the entire thread.
Most of what is considered "celebrating Christmas" has little to do with Christ or the celebration of his birth. That is why many Christians opt out.
Trees, holly, mistletoe, gift giving, days off work, shopping, feasting...
Most of the things we do at Christmas time are not religious, they are cultural.
Cultural:
trees
gifts
cards
lights
decorating
shopping
caroling
Santa, elves, reindeer
the Nutcracker
mistletoe
parties
dressing up
holly, wreathes
cooking special food
having time off work
snowmen
Religious...
Personally, I love the trappings. I love the music, the food, the holly, the presents, the lights, the family get-togethers, the parties, etc. It all brings joy.
I think one of my favorite carols, an English traditional one called "The Holly and the Ivy" may pre-date Christianity.
The early church made a choice to schedule Christian holidays on the same dates as pagan holidays, as part of the conversion of the masses. It kept familiar rituals and times with what was then a new religion. This is a point of fact.
What we consider a modern American Christmas is cultural...