How I grew up.........
Every year my Dad would buy a half of beef and a half a pig from a local farmer. No poison in it....LOL We also maintained a stock of around 20- 25 chickens at all times for the fresh meat and eggs. In addition to that we also ate a ton of fresh fish we caught from the dozens of lakes all around us and generally took a few deer each year from our forests for the fresh venison.
We also maintained a substantial garden each year that produced about every fresh vegetable you can think of. Our garden was around 20 yards wide by 30 yards deep. We gave a ton of it away to friends and family because it produced way more than what our family could eat.
Gee,....I wonder if that has anything to do with the fact that at 62 years old I can walk BACKWARDS faster than most 40 year olds can run,......if they can even run at all THAT IS

But hey,.....keep right on eating your whoppers and Twinkies,.....I'm sure everything will work out just great for you as it not only drains your wallet but more importantly your life.
While a nice anecdote, there are many that don't have any space to raise crops such as vegetables or chickens, they don't know how to hunt, and many don't even know how to fish.
They live in the city, where such things are not commonplace.
However, a lot of what you council can be taken to heart by any city person. Don't buy expensive preprocessed, freeze-dried or frozen, precanned meals and snacks. Buy basic ingredients and learn how to cook.
A 25lb sack of rice will last me for a year.
A 10lb sack of flour will last me for several months.
Bread is less than a dollar in many places.
A jar of jam, peanut butter, butter, or similar to put on it is cheap.
Milk is cheap. Even honey is cheap.
Fresh vegetables and fruit is cheap.
It's summertime. Go out and pick some berries. They grow even in the cities.
Want some pumpkin pie this Halloween? Some flour, butter, canned milk and canned pumpkin is cheap.
Learn to cook.
Spaghetti and other dried pasta is cheap and easily flavored with a can of tomato paste and a few spices, or learn how to make bechamel (country gravy) which is the basis of sauces like alfredo sauce.
It really isn't hard to mix up some pancakes or cook some bacon.
You can even make your own pizza. It's easy. Just some flour, baking soda, a bit of salt and sugar, tomato paste (you can short cut this with italian sauce in a jar), and some spices, and a packet of pepperoni can make quite a few pizzas. I make all my own pizzas. I don't buy any expensive frozen pizza at all. I can put onions on it if I want to. Onions are cheap. Mozarella cheese is cheap.
I make my own lasagna also. Much better than store bought!
Save money. Learn to cook and preserve.