WMG / The Fair Folk

Fey creatures intentionally Disneyfied themselves to be seen as less of a threat to humans.
A couple hundred years ago, the Fey had been happily doing their own thing and messing with humans for centuries, but at one point they realised that the humans keep building themselves sharper swords, tougher armour and big sticks that go bang. Seeing at least some of the devastating weapons to follow, they decided that they'd best avoid retaliation for their 'fun' and being wiped out by changing their image to playful, helpful and cute creatures from Fairyland, and such helpful spirits as the Tooth Fairy and (possibly) Santa Claus.

Seeing things revert somewhat to their old image is probably confusing them a bit, but also at least letting them get a bit nostalgic and go punk rock.
  • If so, then those Jack Frosts are eeeevil. It doesn't help to know Shin Megami Tensei: Strange Journey's Compendium noted they were abominable snowmen who changed forms to more efficiently freeze prey. Naive and a bit silly as they are, they are not always nice...
  • Supported by Recettear: An Item Shop's Tale.
  • In The Dresden Files, it is said Queen Mab paid the brothers Grimm and later Disney to help continue spread the myths and ensure her kind aren't forgotten.

The Fair Folk (as we think of them) didn't let themselves get Disneyfied, they just went underground and let other races do the PR work for them.
Santa's elves? German brownies. Nobody finds out what happens when they don't get paid because Nicholas/Chris isn't that stupid or cruel, and they have no need or want to go to the television stations of the people who make films about elf strikes being unionized or not effective enough. The Tooth Fairy is all that remains of an anti-legend for beings that steal teeth from the garbage or the ground for sympathetic magic, so the children needed to dispose of them in a way that would make it difficult for the fey to get at them; More recent times have parents outright telling the kids to leave the teeth for the "Tooth Fairy" because they don't ken the power of words and intent. Most of the Fair Folk live underground these days, either literally in the case of more feral earthbound races and those who find abandoned human subways interesting places to set up court or metaphorically in the case of those who stop leaving the pet flap open on their hills to keep the squishy, easily-confused, two-legged toys from getting in as often.
The Green Movement, if they've noticed, is simply telling them that all they have to do is wait for us to willingly give up iron... of all kinds. Since we've mostly forgotten about the old ways, it's only a matter of time...
  • If this is at all accurate, then writers like Terry Pratchett whose works contain a fair bit of information on anti-fairy measures have done us all a great service.

Mary Sues are actually subspecies of The Fair Folk.
Unnaturaly beautiful? Check. Reality Warping powers that bend the canon to their will, and makes sure their stories go in their favor? Check. Perfect in almost every way, and thus completely inhuman due to a lack of flaws and relatable traits? Check. With all this evidence from thousands of fanfics, we can safely guess that Mary Sues are avatars or disguised members of the Fey race, whom insert themselves into a story to toy with mankind (and canon) on a more personal level. Mary-Sue Hunter s defeat these creatures by exposing plot holes, bad grammar, and characterization mistakes: similar to how some characters defeat main members of the Fair Folk by using their own words against them.

TV Tropes is actually a gateway to Otherworld. And Tropers are Fair Folk

  • The inhabitants of TV Tropes are invisible.

  • You keep coming here thinking you were only spending a minute and finding you spent the whole day. You must have had the Come Hither placed on you!

  • The inhabitants are obsessed with talking about stories and laughing at them. Are not The Fair Folk famous for their tales? What else would they do but laugh at tales told by mortals?

  • Once you enter here you never leave unchanged. Even your conversation is affected. Is this not said of those who associate with The Fair Folk?

The indisputable conclusion must be: Tropers are The Fair Folk. And they have enchanted you.

The Fair Folk are harmed by cold iron because of its ability to affect magnetic fields.
Perhaps in a similar way to a shark, Fay can naturally detect magnetic fields (possibly an explanation for how they can distort our minds (they're using magnetism to screw around with our brains). Contact with cold iron cancels out this ability, making Fay extremely vulnerable.
  • Supported by Lords and Ladies. "They have what the dwarves call the love of iron, like a compass."

The Fair Folk are harmed by iron partly because they themselves do not have any iron in their bodies.
Iron is a vital element of human blood; perhaps the Fair Folk bleed Alien Blood instead of the substance that flows through human veins. Remember, folklore says that fairies cannot enter Heaven because they do not bleed like humans; one way to interpret this is that fairy veins are filled with something else. Additionally, part of the Fair Folk's disdain for humanity may come from the fact that humans literally have iron within them. A more detailed explanation can be found here.

Cats are a kind of Fair Folk.
Let's see... inscrutable? Check. Can entice humans with their cute appearance? Check. Famously make lulling noises when happy? Check. Sees us as more their pets than the other way around? Check. It's not for nothing that Terry Pratchett gave us the page quote for Cats Are Mean in a book about the Fair Folk.

The Fair Folk have glamoured themselves in the process of Disneyfication in order to remove human protections against them.
Before Grimm, there was a solid body of folk lore about the Fair Folk and how to keep yourself safe. (e.g. stay on the path, don't accept any deals from strangers, cold iron and salt can protect you from their powers and so on...) However Grimm and later Disney diluted and in many cases directly reversed the established knowledge about them. To create a society which believes in the power of wishes, trusts people based on beauty, that if you're a woman that all you need to do is wait and do nothing until a hero rescues you and teaches that running off into supernatural lands will solve your problems. Then when we are thoroughly indoctrinated, they will come back and feast on us once more.
  • This would mean that they are on it a lot longer than we might thought (Beauty Equals Goodness is at least Older Than Steam) and probably hate feminists with fiery passion (seeing what they try to combat sexist tropes like Distressed Damsel and the princess being part of the Standard Hero Reward... both of which tropes are Older Than Feudalism by the way).
  • It is said in legends that the fey like to kidnap beautiful young women (particularly virgins on their wedding nights) to have children with. While young men become the lover to the faerie queen and later to be sacrificed as part of a tithe. They could easily want women to trust beautiful men with the idea they'll whisk you away to happiness and for men to go on a quest for a beautiful maiden (the queen in disguise).

We are the Fair Folk.
Or rather, our ancestors were one of the origins of what ultimately developed into the European concept of fey... through the viewpoint of the Neanderthal's initial encounters with Cro-Magnon (there's some evidence that there during the millenia of co-existence in Europe occurred some peaceful interaction, sometimes extending at least so far as exchanging genes, so the stories could have crossed over at a later point). Consider that from the Neanderthal perspective, Cro-Magnon were tall, slender people looking almost like humans, with strange ways and strange tools (remember Clarke's Third Law and the fact that at least one of those tools couldn't be used properly by Neanderthals, due to differing shoulder structure)...

Tumblr is (also) a fae court on the internet.
Originally from conversation here
The Fair Folk developed space technology concurrently with us.
This is why Alien Abduction and other alien tropes are so similar: it's the same species!

The Fair Folk are a race of Empathic Shapeshifters
Strange abductors have been in folklore for centuries but exactly what these abductors are has varied heavily, even as some elements remain constant. Ethereally beautiful fairy folk for much of history? Bulb-headed grey aliens to present-day conspiracy theorists? Beguiling succubi to Puritans in Colonial America? Perhaps the difference is not in the creatures themselves but their appearance altering to match the expectations of those who view them.

The Fair Folk are- or have somehow become- sterile
... and compensate for their infertility they snatch human children, possibly out of revenge (if we caused the problem in the first place) or a misunderstanding (or, who knows, correct understanding) that they can somehow make human children into their own if they are raised properly.

Fair Folk experience a rapid population boom every time a human subspecies goes extinct
We must all be familiar now with the theory that Fair Folk legends come from time-distorted accounts of aboriginal peoples; some chronicler gets too inventive recording the habits of a small-statured tribe that only has access to stone tools, and they become wee men living among the barrows who are terrified of iron. If you're Doing In the Scientist, then this can be true, but also does not distract from the supernatural aspects of Fair Folk stories- as the real tribe fades away, the fairy story drinks up the essence and sharpens into a sort of half-existence.

The Fair Folk practice extreme selective breeding on their own kind
That's why we hear wildly varying descriptions. Sometimes they're short, crafty tinkerers; sometimes they're tall, willowy, and hauntingly beautiful. If they practiced an intense eugenic regimen, it might be possible that these descriptions, for example, simply apply to the labor caste and the ruling caste of the same species.