Even if we take at face value that this is happening, their margins are famously low (ie. low single digits[1][2]) that any improvements are likely negligible. In the best case scenario where they're run as competently/efficiently as a normal grocery store, but don't take any profits, you'd be saving like 50 cents on a $10 pack of ground beef. Of course, all of this would go out the window if it's less efficient, either due to government incompetence[3], or lack of scale.
[1] https://www.macrotrends.net/stocks/charts/ACI/albertsons/pro...
[2] https://www.macrotrends.net/stocks/charts/KR/kroger/profit-m...