Yes, they exist for test proposes but you can use them as custom spwan.
There are two sorts of NPC that sales items for kinah, that usualy nobody use on on a live server, except as I alreday said, as custom spawn.
From line: 81 to 358, they are custom NPCs, that sale a lot of items, all for kinah, that usualy you must buy for AP or you need to grind. (collecting,crafting, skill book, stigmas, recipes..., even manstones.
All you need are the NPC_IDs from the xml file, you can spawn them where you want.
Just for stigmas you need the npcs from the line: 227 to 287
