They’re nicknacks and trinkets, shiny shangles and dohickies, magic macguffins; they’re not just any old pieces you buy crudely, you’ve got to go out and find them either in the wild or take them from someone else who has. Classic fantasy trope. The engineers don’t want any old lump of pig iron, they want the cosmic element born uniquely in the stellar forge. That’s how I rationalise it, but I always was a bit of a nerd for epic adventures (otherwise known as the slow grind 
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