It's most obvious when agriculture is socialized, because it's impossible for people to believe the lie that they aren't starving.

Yes, I know that communism is supposed to be without a government.

The only entity capable of creating such a market is the government itself. Also, don’t forget that plenty of areas simply don’t operate on a supply-demand basis — e.g. healthcare.

> don’t forget that plenty of areas simply don’t operate on a supply-demand basis — e.g. healthcare

Supply-demand is in play even under socialism.

But here's a simple example. Take your corner drugstore. It has a couple aisles of all sorts of healthcare products, from aspirin to toothbrushes to athlete's foot cream to cold remedies. There are multiple brands with multiple formulations at various price points. How does supply & demand not apply there?

More generally, pick any health care issue. For each, there are a multiple of options available, with varying costs, efficacies, risks, and pain. Including doing nothing (by far most diseases disappear on their own). How is that not supply & demand?