Okay, I know a dog on the opposite end of the scale, size-wise, who LOVES to lick toes!
Bruni, my Dad's Saint Bernard, loves bare feet, and considers them an open invitation to be licked! Dad isn't into sandals, but sometimes has had to warn neighbors who came barefoot to pet "the baby" on their morning walks! I'm sure human feet are at least salty, but not Frito-y, at least none I know personally, though I do not seek out strangers' feet like Bruni does!