This approach doesn't scale though. Its great that it worked for you, truly, but it unfortunately doesn't scale as a reliable way to budget for groceries
What we need is 1000s of solutions that don’t.
Every case is a special case if you treat enough variables, nothing is close in high dimensional space.
Its too circumstantial to scale to even a dozen people in a locality. It isn't that it doesn't scale to the masses, its that it doesn't really scale at all
Precisions farming and decentralised housing and transport are steps in that direction.
I think what you'd find as you scaled it is that you'd turn into ConAgra.