Maybe some ultra fundamentalist or offbeat Christian groups forego all the normal Christmas symbols and traditions, but most Americans enjoy all the symbols, traditions, festivities, both Christian and secular.
I can't imagine denying a small child the thrill, wonder, joy of concepts of Santa Claus and his elves and reindeer and all the other mythology. The concept of the joyous celebration of Christmas is contained in these myths even though the characters and symbolism is fiction.
And I think all Christians who practice Christianity also utilize the symbolism of Christmas trees, the star of Bethlehem, nativity scenes, visitation of the Magi, angels, and other components of the Biblical Christian stories in order to teach children or remind themselves of the wonder of it all.