Not sure if I want to fix that if it's so useful. I did intend for them to convert into a harmless little trinket though. I havent noticed the any hamlets being ruled by actual wizards at all myself, not sure what could be going on there other than worldgen throwing up all the coincidences at you.
In future news, I hammered out a quick setup for the healing school last night, so thats next to be published, but it might still be awhile as there are bugs to work out with that. It'll feature healing of course but also basic resurrection and creating healing undead, and preventing undeath in general. There is also a protection from curses, and standard shielding and buffing spells. I've made this one's reagent a worn amulet of healing and am making sure that works out. For civs with lots of clothing options you probably wont see it literally everywhere, but you might anyway. I know the athames certainly get around (especially since dwarves dont have any other knives civilians can use), so there shouldnt be a shortage of tools for those schools. Not sure what to say about the other tools, if this amulet is alright and doesnt literally flood the world with them they might end up being clothing/weapon type tools too, but you can find them in-game even now, if rarely. Good places to look are storerooms/warehouses, mead halls and bandit camps.