It isn't a return if the goods are low quality and last 1/8 as long. Same with low quality food that ruins health, the cost is externalized to health care
The point is that it is a choice to buy fruits, vegetables, eggs, etc, rather than cookies.
Everyone knows what a poor diet is at this point. Who doesn't know potato chips are not healthy, even in the most poverty-stricken areas? Who doesn't know that brocolli is healthier than Sugar Puffs cerial. Nobody, that's who.