or they can make upgrade-able item for armor and weapon. It has its own durability and can't be repaired, so when it is destroyed, you need to re-apply it.
Armorer = heavy armor
Leatherworker = medium armor
weaver = light armor
goldsmith = accessory
carpenter = wood weapon
blacksmith = iron weapon


so for dungeon crawler or raid fanatics that want to maximize their stats will buy these stuff.