This seems like a very impractical perspective to me. If there really was a "hardware store" that we could head off to to get what we need, it might be differen

This seems like a very impractical perspective to me. If there really was a "hardware store" that we could head off to to get what we need, it might be different. But in general, that's not the case. There can also be significant overhead in looking elsewhere for a solution. That's a big part of why so many developers reinvent things. This is often dismissed as NIH syndrome, but there's more to it than that. You raised "introductory macroeconomics". The economic effect that will most strongly apply in the case of LLMs is that of the technology treadmill (Cochrane 1958): when there's a tool that can improve productivity, it will be used competitively so that those who don't use it effectively, to improve their productivity, will be outcompeted. This seems like an unavoidable result in typical capitalist economies. Your point about leveraging hungry humans would require strong incentives to overcome the treadmill effect. Most Western countries don't have many ways to implement anything like that. The closest thing might be unions, but of course most software development is not unionized.