Sometimes the people who own a territory and therefor the resources in them don't want to gather said resource for each person looking for it or are unwilling to trade the same resource that comes from their industries. This is where land leasing comes in, Town Owners would be able to allow players to gather resources in a specified territory for a certain amount of time, people could manually trade the leases by making verbal agreements for payments etc. Generally it would be a way of allowing people to gather things in your territory for a set period of time.