Caught my older twin daughters wearing shoes without socks recently, shoes making entire rooms uninhabitable etc.
Finally settled on a cleaning spray bottle filled with 91-95% isopropyl alcohol, and soaked the insides down liberally, and any outside exposed cloth that could absorb the alcohol too, and let them evaporate dry overnight. First day cut down the odor by about 90%. Made them wear socks, checked their feet in the morning before school, and then one more application the next night did the trick.
