I see your point about it probably being as clean as "other parts"...but I don't know the arm pit just seems uhhmmmmm "gross". Never tried it though so I won't knock your fetish. But I probably won't support it either.
I wouldn't consider it a fetish, I don't get off on it on its own. It's just a sexy teaser like getting your ear nibbled, in my opinion.
Now, you mentionned chickens. I loooooooove chickens :
I've passed my toung across my last girlfriends whole body. I even licked her eyeball. She kind of freaked for a second but she eventually laughed about.
i'll lick them; prefer them shaved/trimmed, but in the heat of the moment of the armpit is attached to a great bulging bicep/tricep and the chest is massive, yeah, I'll do some muscle worship with my tongue that will go up there into the pit.