Fallacy.
See Motley Crue.
Fact.
See Little Richard, Boy George, David Bowie (though he was an equal opportunity swinger), Freddy Mercury, and I think Bret Michaels is trying too hard to overcompensate. And his drummer was named Rikki Rockett.
And even if KISS was straight, their genre of music was still called "glam", which carries a certain stigma with it