I obsess over price per ounce of my food while I am in the store. (Though it gets harder as I age and my brain weakens, and as prices and sizes get intentionally harder to compare)
Even still, I myself that groceries I eat are super cheap compare to food I throw away and restaurant meals. (And I avoid packaged meals and name brand cereal, which are near restaurant priced)
Every now and then I remember that the vast majority of people don't or can't think about food costs, and shudder. Paying $2 for a bottle of water with a scoop of sugar poured in. $5 for a box of Kellogs instead of $3 for generic. $4 for the frozen brocolli with fake cheese sprinkled top instead of $2 for plain. Etc