I think you sort of have to look at how SNAP evolved. It was the result of what was deemed to be an iterative series of improvements. Way too low-res, the sequence was "commodities" to food stamps to SNAP, with generics and store brands also evolving out of the same ferment.

SFAIK, the principal ... principle driving this was administrative cost reduction on the government side - reuse existing buildings and people.

And then it ties into the crop subsidy system, which is generally awesome in that it prices risk from shortage almost to zero at a cost in mild to "OMG!" overproduction.