Because fairies are supposed to be effeminate and cute?
Notwitstanding the fact that gay men aren't necessarily like this, I say it shouldn't apply even to the effeminate ones.
Remember how we used to think of fairies.
Remember that people used to hang charms on cradles to prevent the fairies from stealing their children.
And you weren't supposed to step into a ring of mushrooms, because it was a fairy ring and if you stepped in you wound up dancing forever.
And if you offended them they'd curse you, and if you pleased them they'd reward you, and sometimes it was hard to tell what would be an offense. Although Jack Madden should have known that interrupting their song was a bad idea.
They didn't really mind harming humans. They would lure you over cliffs and confuse your path across a field just as soon as reward you. Being pixy-led is not a happy thing. Oh, they were charmers, they were, masters of illusion. You could think you were helping deliver a baby in a massive and fancy mansion, and it would turn out the mansion was a cave full of moss and mold.
Things like that. Things like women who washed bloody clothes in the river, and if you saw them somebody you knew was dead soon. Maybe you. Shrunken gods of old who had once driven giants out of the land, and now held parades to remember their faded glory. Little house-helpers who would vanish at the first sign of praise. Horses that would trap you on their backs, then drown you and feast on your bones.
And yet, if you knew their ways there were rewards. You might find gold, or good luck. The Knockers, in the mines of Cornwall, would work close to human tunnels, and warn folk of cave-ins. Sometimes if you followed their sounds, you'd come upon rich lodes.
I heard fairies described once as beings of air and fire, as opposed to humanity's water and earth. And one thing both air and fire do is change shape all the time, dance about quite randomly. That would explain a lot.
And if ever you came to their realms, by your own will or by force, you would come back and find that hundreds of years had passed, or no time at all. Mind you didn't step out of your conveyance, though, because if hundreds of years had passed, they'd catch up to you as soon as you met the earth.
But some of their blessed isles, beyond the setting sun, were so wonderful that you wouldn't want to leave.
And you call a gay man a fairy?
I've never known a man to act like that.
I've never known any who could even come close.