I think among all your examples, the Santa Claus story is unique in our society in that adults tell it to children with a completely straight face and actual intent to deceive.
Apparently so; but not the intent to maliciously deceive — to deceive in order to weaken and exploit, in the manner of a con-artist or quack.
My point was that the intended epistemic status of statements made in everyday life, especially around children, is not all that clear. It requires analysis — indeed, literary analysis — to figure out what is a truth claim, what is a fictional canon, what is a parable or metaphor, and what is just pure pretend.
People cry over fictional deaths — children and adults, too. That involves some sort of participation, suspension of disbelief, or perhaps entering into the story (eitsing, a possible antonym of Hofstadter's "jootsing" or jumping out of the system). This is not unusual or pathological in the slightest. It is a normal part of human culture.
Being able to drop into a role, participate in play-acting or ritual, and so on — that's a social skill.
And they get angry at adults who tell children the truth about it. Or children who tell younger children the truth. Or sometimes even children who admit knowledge of the truth.
Maybe this is the point on which the apparent disagreement here turns. I'm aware of the story that parents do this, but I've never actually seen it — neither in my own (Christian, American) upbringing, nor others I've seen.
Mind you, I have seen parents be upset when someone mocked their child for thinking Santa was real, or made the child disappointed or anxious with the revelation. But that's a bit of a different thing; the upset seems explicable by the child's unhappiness.
But the idea "many or most (Christian, American) parents actually become upset when their kid finds out that Santa is a story" seems to me to itself be part of the story.
I have no evidence for 'most', and no hard evidence for 'many', but I can tell you I've witnessed it, so I have evidence for 'more than none at all'.
Related: The Santa deception Is Santa real On the care of young rationalists
All of the other takes on this topic start from a point, when a child (usually 5-9 years old) asks "Is Santa real?" Nobody yet asked "how to raise my child Santa-free?" What to say, when a two-year-old, who just noticed that there is this character on TV asks "will he come to me, too?" A toddler may not yet understand the concept of lie, of pretending, of things not physically existing. How to tell her, what will happen, what to expect, how and why other children behave differently?
My three-year-old daughter discovered Santa last spring, which finally forced me to think: how to deal with it? Ignoring the thing worked for three years, but what now? I live in an extremely catholic country (Poland), so I cannot be completely blunt about it.
In the end I decided to call it "the fairy-tale of [Santa] Claus." For me it has a lot of advantages: this is a story that can be told, retold, reinvented and everybody knows it. In addition, since the name includes the phrase "the fairy-tale", it has just as much validity as the tale of the Red Riding Hood or any TV character that she likes.
I tested some of her beliefs about "Miko". I opened the box with books intended for gifts in front of her. When she wanted to read some of them, I explained that she cannot yet read her book, because she'll get it on Christmas Eve. She asked "is it from Miko?" and I replied that in some way it is, but I bought it. She didn't insist on reading it right now. A few days ago she helped me wrap some of the gifts. She commented that action "Miko brought these so we can wrap them and give them as gifts from Miko."
Malcolm told me, that he likes best the strategy, when you say that Santa Claus is a game that everyone plays. People pretend that there's a big guy in a suit who does the thing, and if you ever let down the pretense to your friends, you lose the game. I'm not entirely convinced by this strategy - it may be too complicated for a 2- or 3-year old (since my daughter didn't wrap her mind around the information that I bought the books).
What are other strategies that you use? Or which ones you don't like? Why?