That is what we used to go through in a week, year in and year out, when my four kids were growing up. Of course we ate other things too, but those three items were permanently on the grocery list. At least, the bread and milk were; after a while I began canning my own jam. My yearly goal was to can 50 half-pints of strawberry jam, as that was the family favorite. I finally accomplished it the year before DS1 graduated and left home.
We also easily went through an entire 250 pound (on the hoof) hog, and three deer in twelve months. Twenty four chickens? No problem. Ate those too, and then some.
I got really good at taking recipes, most of which are written for 4 servings if they are an entree, and multiplying them. DH and I used to joke that our kitchen, with it's 5-burner stove and extra large pots and pans, looked like I was cooking for an army.
Then the kids started to leave home. Honestly, we didn't notice much difference in food consumption when DS1 left; mainly because DS2 and DD1 were hitting their stride as teenage eaters right about then. But when DS2 left home, I realized I didn't need to multiply recipes anymore. Not unless I wanted to put some in the freezer for future use. I could even get away with only buying milk twice a week!!
Two months ago, after DD1 moved out and before any hint of DS1 & family moving back in, DD2 asked me what I would do next year, when she goes off to college. With only DH and I to feed, would we eat the same dish two days in a row in order to use it up? Or would I put half into the freezer? Would I start buying milk by the half-gallon so it didn't go sour before getting all drank up?
We were down to drinking just 1 gallon per week at that point. I figured I could probably get an entire gallon drank before it went bad, if I bought it with a far enough out expiration date. Or, maybe I'd just talk to the friend a few miles over that got dairy goats this summer. . .
Then everything in the south (Carolina, that is) went south, and I find myself in not a household of three planning to go down to two occupants before the next ten months is up, but in a household of seven. Thankfully one of the seven isn't on solid food yet!
Fortunately, cooking for six is still pretty natural to me. Because, with DS1, K2, and K3 all eating here daily, we are back to four loaves of bread (made now, not boughten), seven gallons of milk, and a half-pint of jam each week. An entire hog would be most welcome in my freezer. And three deer also. I'm all ready running a little short on chickens.