Mistake in "Miracle on 34th Street"

In the Best Christmas movie list it's in the very firsts positions because there is no Christmas without Miracle On 34th Street and the 1994 version with an outstanding Richard Attenborough is amazing. Everything seems perfect: location, light, sound, actors, direction, and the script is a bit expected but really good.
Except for one thing, one little particular that is completely crazy for how much simple it is.
The name of Santa Claus.

There is no Christmas without Christmas movies

There is a scene at around the 23rd minute in which the little star sits on Santa Claus' knees and ask to him his name. This is his answers:

Well, I have lots of names. Uh, Kriss kringle, Santa Claus, Father Christmas, Saint Nicholas. If you were in holland, I'd be sinterklaas, or in italy, le befana.

What? Almost everybody knows that in Italy we call Santa Claus with the name of "Babbo Natale" while "Befana" is the name of the old lady that comes during the night of the 5th January to bring carbon to bad children or sweets and candies to good children. Befana is the character that we Italians have invented to give a pagan meaning to the Christian holiday called Epiphany, when the Three Wise Men went to the Jesus' grotto following the comet to bring their gifts to the new King.

I'm old, please, understand me...

The question is always the same, exactly as it was in "Maria Antoinette" by Sofia Coppola, where in a scene there was a first shot of a pair of Converse shoes. Converse shoes in a movie based in the eighteenth century?

What??????

And the question is: how is this possible? A movie has been watched by thousands of people before it's been released and possible that nobody has asked to himself: what are the name of Santa Claus? Or, is it possible that nobody has seen this pair of shoes?
It's crazy, isn't it?