Sure, big grocery stores have low profit margins, but they make money by selling large numbers of items in multiple locations. Smaller grocery stores can see higher profit margins through intelligent inventory management, excellent customer service, and savvy store management.

Chemistry is central to the history of how we produce, store and consume food, from preservation, pesticides and quality testing to artificial additives and substitutes. And the art of cooking—transforming the qualities of ingredients and how they combine to form new textures and tastes—is itself a chemical process.

Then, on September 11, 1916, in Memphis, he opened the first supermarket in the world, Piggly Wiggly. In his new supermarket, the customer no longer had to give a list to a clerk but would pick their own items.

Grocery stores get their produce in two ways. They either purchase fresh fruit and vegetables directly from farmers or buy them through grocery distribution companies. There are grocery distribution companies specializing in just produce and distribution companies specializing in specific grocery items.

A good example is the supermarket. The supermarket operator decides his retail prices—sometimes at near the wholesale or farm prices and sometimes at much higher prices. Anyone who has observed the relationship between retail and wholesale prices has seen this in both individual retail and chain stores.

In carrying out its function, a supermarket business acquires and assembles a wide assortment of goods from individual suppliers, then organizes and distributes them as-needed to a chain of retail stores for sale to local customers.

Supermarkets typically are chain stores, supplied by the distribution centers of their parent companies, thus increasing opportunities for economies of scale. Supermarkets usually offer products at relatively low prices by using their buying power to buy goods from manufacturers at lower prices than smaller stores can.