I think there are at least two other reasons, too:
One, sweat equity matters. I know I value pieces of furniture I built myself more than furniture I bought, even though the furniture I bought is better quality - because what I made myself represents my skill and my labor and my commitment. And in a throwaway culture, creating that emotional commitment to clothing or furniture or a home matters.
And two, rammed earth tires require no supply lines, no 3D printers, no expensive tools or complex chemistry, no gas or electricity, even. Just used tires, local dirt, and local labor. If global supply chains fall apart and resources get scarce, people can still build Earthships - and the people who are building them now will be able to teach others how to build them in the future.
I think there are at least two other reasons, too:
One, sweat equity matters. I know I value pieces of furniture I built myself more than furniture I bought, even though the furniture I bought is better quality - because what I made myself represents my skill and my labor and my commitment. And in a throwaway culture, creating that emotional commitment to clothing or furniture or a home matters.
And two, rammed earth tires require no supply lines, no 3D printers, no expensive tools or complex chemistry, no gas or electricity, even. Just used tires, local dirt, and local labor. If global supply chains fall apart and resources get scarce, people can still build Earthships - and the people who are building them now will be able to teach others how to build them in the future.