Umm, depending on diet, there can be some cost-savings. I have done a few comparisons from restaraunts I frequent and cost management. I have also, barring some freedom in prep/leftover calcualtions, have shown that I can get some great cost savings by going out. I don't eat steak every night. But I do try to eat nutritiously. Prep time/resources/storage/utilities can be expensive depending on where you live. Also, people who live in apartments have distinct disavantages when trying to buy in bulk and store the supplies. But I don't recommend living off of cheeseburgers or trying to eat at Outback every night either.
To start off, the writer does not include a tip, which raises the price on every meal, from meal-to-meal:
A) I am guessing the soup is for a can of whatever they had at the restaurant. A can of soup to me (and a sandwich) is a whole meal. I am not eating a can of soup with a steak, salad, and vegetable side. Also, does one expect to eat a whole bag of salad themselves in one meal? Why buy a bagged salad? Buy the ingredients separately. And who eats the whole bunch of asparagus?
B) I am willing to believe the seafood prices were for the meal only (at least in the midwest, it's what I'd expect to pay). However, $1.99 gets me a whole box/bag of pasta. I don't eat all of that in one meal. Same comment as before with the salad, similar scenario with the breadsticks.
C) I don't eat an entire box of wild rice. I am guessing they used boxed mashed potatoes which are just disgusting and it's cheaper to make it yourself. And I don't eat a whole head of brocolli which is what I am guessing they priced for.
D) I won't eat that entire flank steak myself, at least not in a meal like that. Brocolli and rice comments made before.
E) Same comments on potatoes and carrots as before.
What was the science behind finding these numbers? The writer probably did the shoddiest job they could with their explanation to fit the needs of their conclusion. This has nothing to do with buying in bulk.