She and her husband have SEVERAL mouths to feed so I'd rather not see that grocery bill.
But if they do all their shopping in the produce and deli section... it may not break out as bad as it seems.
The best part is likely little to no goes to waste. Most people get on a kick and buy a bunch of produce and probably 1/3 to 1/2 of it will spoil.
You can't buy cheap produce either, unless you are eating it quickly. Like if you buy bagged shredded lettuce, it's spoiling in the bag, that's meant to be eaten within a day 2 of opening. Which isn't a problem if you have a house full of people. But then again, you also can't buy a weeks worth at one time and just load it up and dump it in the bins. Whereas if you chop a head of lettuce and preserve it right, that'll last.