April, what a very interesting article! I was born, raised and have lived in the South my entire 60 years and have never heard of a Shoe Tree! What a sight that must be, a tree clothed in shoes of all kinds!
A couple of times over the years, I have seen a pair of sneakers hanging from telephone wires and always wondered why someone would throw their shoes up there. I always thought maybe it was kid's pranks. I could visualize two young boys walking home from school, fooling around and one taking the other's shoes, tossing them in the air and the shoe laces catching on the wires. I always wondered what their mama's were going to say when they told her their shoes were hanging on telephone wires and they had no way of retrieving them.
I like the idea that maybe these discarded shoes in trees have become homes for the birds. After a few rains cleaning the shoes and maybe taking away that sweaty foot smell, it's possible bird families have taken up residence!