Exchange Exemplar: how your food gets to the grocery store
It's on the shelf, you give it a look, and if you like it, you buy it.
The consumer end of grocery shopping is really quite easy in today's world. But oh, the work it takes to get the food to the grocery store, and the work it takes to keep the shelves stocked while it's there, to say nothing of the supreme contributions made by non-human animals.
We were just becoming aware of the term "supply chain" when Benjamin Lorr explored the food supply chain in his book The Secret Life of Groceries: The Dark Miracle of the American Supermarket. From the farm to the Piggly Wiggly, he covers the movements of today, and the innovations of yesterday that established the current system.