>>54627116The armpit slopes down and naturally draws the eyes to the breasts, while also accentuating the slender, feminine shoulders. Its also a source of sweat, and therefore pheromones.
Meanwhile the foot is just a foot. Dirty, rough, not connected to any other secondary sexual features. Its not a coincidence that the top Pokewaifu, Gardevoir, has no real feet, just standing on the toes.
tl;dr footfags have a screw loose while pitchads appreciate the more subtle beauties of the female form.