Correct. It's counter-intuitive.
Consider -
Fresh fruit and veggies cost more than canned or frozen. (Most are preserved in solutions with salts & sugars)
Buying your own ground beef costs more than frozen burgers with carb additives.
Roasting your own chicken on the BBQ costs more than a prepackaged bird at the market's "hot table".
And DYI takes a lot more time as can be noted from other posts here.
Grocers have a vested interest in you being addicted (for lack of a better word) to sugars and deprived of fats - it increases their bottom line while increasing your waist line.
Ouch.
Carolyn