What a perfect way to price the poorest people of society out of the most valuable resource - food.
Assuming your time and transportation has zero cost. And even then you're going to have to be buying pretty massive quantities to get a big enough of a bulk discount to even have a chance to make yourself a burger for anywhere near $1.
The study found that living in a poor, mostly black neighborhood presented "a double disadvantage" in supermarket access. Unsurprisingly, poor black neighborhoods had fewer supermarkets than wealthier black neighborhoods."
http://articles.latimes.com/2013/oct/30/science/la-sci-sn-po...
Plus, a lot of poorer people already work at these places, so it's pretty convenient and cost competitive to the products from CVS.