One of the hallmarks of pre-industrial societies, before the advent of mass production and modern distribution networks, is that people could specialize in and make a living from selling a very narrow product line. There were no Wal-Marts, not even general stores. So if you wanted shoes, you went to a shoe salesman. If you wanted a nail, you went to the man that sold nails. People were known by what they sold; they often did not have store, just a booth or perhaps they were traveling salesmen selling their wares to passersby. Here is an extreme example of specialization: this man doesn’t sell fruits, in the plural, he just sells lemons. That’s it.
His entire stock and trade is on his back as he walks down the sun scorched streets of Athens in the early 1900s, selling lemons. Just lemons. And if you wanted lemons, I suppose you would have to track him down whatever street he happened to be on that day. It is hard for us to even imagine a world where shopping is conducted this way.