And attending people travel on foot, sleep in tents, hunt and gather their food while the conventions are held outside in a clearing of the woods or you need so

And attending people travel on foot, sleep in tents, hunt and gather their food while the conventions are held outside in a clearing of the woods or you need something non-ephemeral such as hotels, restaurants, roads, etc.? The vessel was also (hopefully) non-ephemeral and lasted for many expeditions, but needed repairs, maintenance, etc. and likely its captain and crew were capable of sailing because of the years of experience. While organizing a convention or a trading expedition can be ephemeral, it is only possible because all the other non-ephemeral and needed businesses exist.