Just an idea,
How about using a staff as a fake customer to place orders ?
Not the ideal solution, but a solution.
Anyhow, I think there a lot of potential to add new features to reach the status of a full Restaurant Management System. There has been other requests for internal management (internal table management, table joining/splitting, kitchen management, ...). I am sure Sam (or some other programmer) will come with such feature in the future.... :)