PSA - Shoe services for amputees & peeps with mis-matched feet
For individuals who only need one shoe, there are many organizations that accept donations of single shoes in good condition and/or may be able to assist in locating single shoes.
There are also retailers that offer single shoes (or pairs of different sizes) for sale or for significant discount.
And if you have (athletic) shoes too worn out to donate?
"Nike developed the Reuse-A-Shoe program in the 1990s ... to transform the recycled shoes, along with pre-consumer shoe waste, into Nike Grind: a material used to create athletic and playground surfaces and more."
Huge h/t to @troublewithwords who took my casual comment & tracked this down!
https://amputee-coalition.org/resources/shoe-exchanges/