Think of it this way. Mass production is completely star wars why build a droid when you can build a trade federation droid army roger roger. Why build one clone when you can build a clone army. Why produce 1 correllean cruiser when you can produce a fleet. Why ship one dose of spice when you can fill a cargo hold. The supply isn't inexhaustible but the more common the resource the easier it is to get.
If you want to make soap sculptures well soap is pretty **** common. If you are a leather worker in the star wars world there are an awful lot of creatures killed for food which give the byproduct of leather. That's what rarity 0 represents. Cow hide wood for arrows very small rocks mud for ceramic ship components. There just is so much of it you never really have to worry. If it makes you feel any better the system won't let you build 71 suits of power armor so easily and getting that much stuff would take an entire campaign and cost hundreds of thousands of credits.