Dave, sounds like you and I were in the same line of work for a while. My Uncle was a DVM in eastern Oklahoma, and several times I made "totes" out of old boots, carried the same things you did. Flash forward a decade or so - my kids were totally awed when I would ride the horses with nothing but a halter and lead rope on them - or grab the head of a nasty Brahman bull and put him on his back. Fool bull never messed with me again!
Doc collected old medical stuff, had an early copper syringe from 1810 or so.
Even today, I hate to toss out anything that may become useful at some future time. My kids, grandkids, and great grandkids will have some work to do when I finally pack it in.