Ha! I had a good laugh from some of the posts above.
I put a pinch of corn starch or foot deodorizer in every pair of socks that I bring on a trip, and a big sprinkle in my main pair of shoes. I'm always afraid that I'll be the last one to notice the stink. I'm the mother of a teenage boy, and he appears to be impervious to his own, rather pungent, feet and footwear.
I like to have my feet in sandals, especially on long flights. I try to change my closed shoes in shower area of the lounge or in the loo, and will wash my feet with a damp towel in the lav, then wear my sandals on the flight.