Just go barefoot! I always enjoy the oxymoron (and irony) of buying "barefoot shoes" :-) Sounds like paying for "invisible clothes."
Bare feet never have a problem of getting stinky, moldy, or otherwise gross.
I run in bare feet, period*. Saves me from knee problems, joint problems, and hundreds (thousands in a lifetime?) of dollars in replacing running shoes. At work I wear professional shoes. If I'm out and about going into stores, etc., I wear a $1.00 - $2.00 pair of flip flops in warm weather, or whatever shoes are appropriate for the weather or event.
* Full disclosure: In very cold weather, I run in "aqua socks" along with a pair of regular socks, purchased for $8-10 at Target. They are equivalent to the $100 Vibrams without the funny looking gorilla toes. Keeps my feet warm, offers zero artificial support.