The thumb tip began being used by magicians in the late 1800’s and it’s actual creator isn’t exactly know, there are two people that clam it’s use. Recently I was at a museum and they had some Egyptian finger and toe caps:
These are essentially thumb tips, but used for decoration, and not for magic. There’s a lot of stuff that exists in the real world, that magicians notice and start to use for magical purposes. I wonder if these could have been the inspiration for the thumb tip?
We’ll never know for sure, but they sure do look usable!