What over-the-counter cream treats foot fungus?

They can: There are a variety of over the counter creams and sprays for treating athlete's foot. Most of them are generally effective for mild to moderate disease. I would suggest trying one of the sprays and remember to spray it in your shoe as well as on your foot to help kill any fungus living in your shoe. Incidentally, Vicks vapo rub seems to help for nail fungus and skin fungus. Use it twice a day.

Lamisil (terbinafine): Lotrimin (clotrimazole).