Watching the grocery store cashier ring up your food items, makes every working-class shopper rethink that second box of gourmet cookies. As the receipt tallies your haul of hunted and gathered groceries, it's hard not to think of those days when a family of four could live off of a $20 grocery store run for a whole week– nowadays, $20 gets you a box of lettuce, 12 eggs, and a cluster of bananas (if you're lucky).