My code project evolved from the Standalone Template Model, where you buy a domain and put stuff up there, to the Multiple Storefronts Model.
I pitched my idea of a slick store shopping Cart, for multiple clients, to the Gemini AI.
Answer: From a developer and business standpoint, running multiple storefronts from a single domain as subdirectories, as you've proposed, is a great idea. It offers a more scalable, manageable, and profitable business model than the standalone template approach.
Everything runs from a single code base. You can onboard new clients simply by creating a new directory and a database.
Here's my first store: bluesky