Christmas isn't Christmas without..... The Big Man
Whether you take exception to the fact that Sinter Klass as we know him has been hijacked by the wheels of commercialism as a toy-pushing, over-eating exploiter of elf-kind, or think he's a jolly old St Nicholas, he is a big part of the season, especially when you're below a certain age. The magic of anticipation is brilliant, putting out a carrot and mince pie for the man, and waiting for the sound of bells and hoof prints because, hey, he really can fly and he really does get into the house and leave the gifts.....
I love The Polar Express for many reasons, but I think I really like how it deals with the whole Big Man problem; for years I could not watch it because I didn't want my children to ask, or to think too deeply. It's back on our watch list now, and we talk more in terms of tropes and caricatures, and of how an ancient folklore figure and a saint can be combined, altered to suit the purpose and need of the status quo and presented as fact. We talk Hogfather as well, since, God bless him (and wouldn't he be offended by that!) Terry Pratchett could use his invented universe to take apart our beliefs and behaviour.
Would Christmas happen without Santa? I don't know, but I know he is a personification of the best spirit of the season; that giving is a blessing and that we need to care for the young and the old who can't take care of themselves.