> Markets provide availability of goods, as long as you can accept price variability.

Not if the vendor goes out of business.

> Food is a bad example, as availability is ultra high. Fresh produce is scarce in areas due to low demand. Low demand leads to higher prices.

That's not the case, based on the reports I've seen. What have you seen that supports that?

Unless we are in a monopoly situation there are other vendors for common goods.

If a super market goes out of business there are several others though perhaps further away.

The idea of "Food deserts" is around the poor availability of affordable "nutritious" food. There is plenty of food in these food deserts with many different food providers.

So it's not about general food availability, it's around what food is stocked. Which food are stocked is almost completely determined by supply and demand. We know the supply exists, so if there a lack of stock it's due to demand.

What other explanation is there ? A shadowy cabal making sure the poor can't access certain foods ?