How does the government manage the physical space of the economy?

Did you buy something today? Let's suppose you bought a pencil. What brand? What color? Did you look for a certain pencil or just take one from a display near the checkout?

Multiply all such decisions by everybody in an area and you have the economy of that area, measured in the local money. You might also be concerned about the economy of food or water, and a diver would be concerned about the economy of bottled air.

Economy means management, as in the class called "Home Economy". When you speak of a physical space of the economy, I wonder what you talk about.