When I was a young man, I avoided washing clothes. I wore my socks to work several days in a row, and only washed them when they became crusty. I never saw it as a big deal, but eventually, my roomate noticed my foot odor. I thought I might need to get some powders to handle the smell, but I was wrong. My roomate gave me a tip which helped me stay odor free from that time forward. Every time you put on your shoes, or switch from one pair of shoes to another, do so with a clean pair of socks. Even if it was only 30 minutes since I took my shoes off, if I was putting shoes back on, it was with a fresh pair of socks. That's all it takes to prevent foot odor from forming.
It happens to me that I use a pair of socks for a short outing and when I return I put them away, obviously I don't put them together with the one I haven't put on yet and they are still clean, but they are waiting for another round, but if it has been a long outing, where I walk a lot, or a full day of work. I would give those socks one use only.