You do what you have to do in life, when you form a philosophy that you can't talk yourself out of.
If we were to wake up some morning and find that everyone was the same race, creed and color, we would find some other causes for prejudice by noon.
The Polar Express is about faith, and the power of imagination to sustain faith. It's also about the desire to reside in a world where magic can happen, the kind of world we all believed in as children, but one that disappears as we grow older.