For the mathematically challenged

Dollar stores are made for people who are trying to save money, but can't be bothered (or just can't period) to do the math on why their offerings are not a good deal.

For every $1 in sales, Dollar General and Dollar Tree earn an average gross profit of ~$0.30. That’s more than rivals like Target ($0.28) and Walmart ($0.24). These stores also buy bulk surplus and discontinued items, further increasing their overall profit margins. That $1 Old Spice deodorant might seem like a good deal. But at 0.8 oz., it's less than one-third the size of the standard 3 oz. stick, and on a per-unit basis, it's significantly more expensive than the larger sized offerings at other retailers.

Dollar stores are targeting demographics who either aren't educated enough to spot the scam or who don't make enough to have much choice in where and when they buy their household necessities.

You don't reach 34,000 stores across the US, with a new location opening roughly every 6 or so hours, by operating at a net loss. You do so by tricking your customers into believing they're getting great, cheap deals on name-brand items, when in fact they're simply paying more for less product.