I don't have kiddos but, when I was a kid growing up, the idea of Santa was magical.  The siblings and I would try to stay up all hours and catch the jolly, red-suited man dropping down the chimney to load up the loot.  Never understood not hearing him park the sled on the roof.  Great times.

Maybe I'm projecting, but when I found out that Saint Nicholas wasn't really bringing gifts I started to wonder what other lies my religion was responsible for. Put me down a dark track.

How old were you when you started wondering about the lies of your religion?  Seven?  If you don't mind me asking, and you don't need to respond, what 'dark track' did the Santa Claus story send you down?

We never taught our son that Santa Claus was a real person, nor that he brought gifts down the chimney on Christmas Eve.  We followed the Polish tradition (I'm not Polish, his mother is) of St Nicholas having been a bishop, and that men dressed as St Nicholas (or a whimsical approximation thereof) brought presents to children.  So our son never had a lie which he had to unravel and discover the truth of the matter.

I find the Santa Claus myth to be a wrong-headed Protestant invention, yet one more way in which they take a Catholic tradition and utterly butcher it beyond recognition.  All Hallows' Eve, mutated to Hallowe'en, is another such instance.  Outside of Anglican and possibly Lutheran circles, Protestants have no clue as to what All Saints' Day even is.  Their view of Christmas and Easter is only slightly less obtuse, in that they realize there is some religious aspect to their origins.

Simple.  We grew up knowing that Santa Claus was actually St. Nicholas who is a Saint who actually did give gifts.  The commercialism surrounding him came from Thomas Nast’s, The Night Before Christmas, which we knew was as real as Rudolf the Red Nosed Reindeer and later, the Grinch, IOW, that part was fiction, just for fun, nothing of religious belief.  

We told our children that Santa Claus was fictional character based on Saint Nicolas, but transformed by the americans to sell coca cola. They have never believed in this Santa nonsense, and, when younger routinely opened the eyes of other fooled children, making conspiracy theorists of them all. 

Santa is used as a fun aspect of the holiday but I never told my kids he was real. They are familiar with St. Nicholas since we read the story on St. Nick's day. 

As a child, I recall the only instance that had any major dealing with St. Nicholas, or Swiety Mikolaj, as this is a Polish story. 

I believe there was a to-do at our Polish Hall that reflected in some ways La Pastorela. I do recall angels and demons. Then Sw.M. would show up on stage, and all the children would go up and receive a HUGE bag of nuts and assorted goodies. St. Nicholas always remained as part of the Christmas pastiche but he never overshadowed Christ and His Blessed Mother. I do recall as well along the lines of St. Nicholas giving small gifts as the birth of Christ was (and is!) the GIFT at Christmas. 

I did get my picture taken with Santa Claus in my early years. In those days, you would never see any Christmas decorations or Santa castle/sleigh until late November or early December. Twere magical days indeed, in the sense that I could palpably sense the spirit (the grace of the holy season) of the Yuletide. The Twelve Days of Christmas, beginning with the Polish Christmas Eve celebration, were truly perceived as a different space in time. 

I never married thus no kids and Santa is but a large candle who is not prominently placed, although visible. I do believe we have a Father Christmas figure that belonged to my mother - a gift given to her. Santa is a non-persona amongst some of the children I know from our neosspx mission. 

As for the other side or part thereof of the mythos accuмulated around St. Nicholas, I do know we were taught the various European traditions surrounding him and Christmas in my primary/elementary days, so I was aware of Black Peter. I only heard of Krampus when I taught at a Society school. I ended up being St. Nicholas that year, with one of my high school students being Krampus, although no where at overt in costume as that particular figure is portrayed.