They are keen when you are stiching up a shooting pouch.
I know I have seen a modern drawing of a stock being worked in a shave horse, but that may only be artistic inagination.
Nice piece of equipment though. I would suspect that the hole in the middle of the seat held a metal tool tray (like a bowl) to lay harness needles, thread, leather sewing palms, pliers, and maybe a trimming knife. If it were mine, I would add the tray and a partially stiched pouch that could be used to demonstrate saddle stitch.