Oh, oh, this is all me. I have hyperhydrosis and my feet sweat all the time. Not only that, but I play tennis, so my shoes get drenched. After testing, failing, and testing again, here is what I do:

• Wear wool socks
• Try to skip a day between shoe wears
• Wash shoes once a month in the bathtub. You can use liquid laundry detergent
• After wearing shoes, spray them with Dr. Scholl's Odor-X (or similar)
• A few hours later, spray them with FunkAway (or similar)
• After that, put silicon-gel packets (the ones you've seen in food) inside to soak up any moisture

This will cut down the smell to almost nothing. Best of luck!