A person can actually live on about $1.50 a day, food-wise.
You won’t get fat, and you won’t be eating any filet mignon, but you won’t starve!
Agreed. I would prefer not to, but a 20 pound sack of rice will provide 5 days of cheap calories for a family of four. Throw in some Spam, sauces, and canned veggies, and you've got an adequate emergency food supply for ten days. Repeat as necessary, substituting pasta, flour, corn meal, potato flakes, or other cheap starches for the rice, but still including a variety of supplemental foods. Add some seeds and a garden, and a way of harvesting small game for fresh meat, and it's sustainable.