@Martin A. and @Steve Bullman,
Afraid my knowledge of what the maps can and cannot do is limited, so maybe some form of restriction from entering a postcode, street name or physically dropping a pin? So this would force the user to only type in a town, city?
However if that is possible, maybe consider some form of user group based permissions...
For example I would want to restrict my members to protect their privacy etc, but I have Club Sponsors who as a business would want their exact location pinning and I would consider having pins for events/meeting locations etc.
Regards
Jim