I went by the farmers’ market the other day and a stall had duck eggs for $8-10 a dozen. Buying 36-packs from Walmart is maybe about $1 a dozen. I don’t see it going much lower than that, or higher than $20, though.
For a while now I’ve been fairly convinced that everyday expenditures scale logarithmically with income. The increase is pretty smooth, and tapers off pretty smoothly too.
I was reading a scientific article a few days ago about mealworms (of course), and the process by which they extract water from the air. Turns out it more than doubles their metabolic rate just to do that.
So even the biomimetics isn’t going to get us very far on this one.
The kind of solution you’re looking for involves moist soils with high levels of organic matter. That, and using less water for economic activity.