～足
～そく · ～soku · JLPT N2 · noun
place
👟 足 = foot, so you count shoes by the feet they cover
足 (soku) also means foot or leg. A pair of shoes counts as one 足: 靴一足 is one pair of shoes. It covers socks too, since both are things worn on the feet.
足 — top 口 (mouth/enclosure) + bottom 止 (foot)
Originally a pictograph of a leg and foot, with the upper square representing the knee or shin and the lower part 止 depicting the foot itself. It primarily means 'foot' and by extension 'sufficient' or 'enough,' a meaning shift likely from the idea of standing firmly or having a solid footing.