All signs shall be located on the same property with the use, firm, facility, business, product, service or organization they advertise, unless otherwise provided in this section. Exceptions include: campgrounds, and similar permitted natural resource-oriented businesses located off or not visible from a major thoroughfare, shall be permitted up to two off-premise directional signs no larger than 16 square feet each, provided such directional signs do not contain advertising and are restricted to the name of the use and any necessary directions.