What they really need to do is come up with a "preferred tourist visa", where people (regardless of national origin) are only able to get this after being interviewed to make sure they're properly respectful of the local culture and environment, and if they get caught doing something wrong (like littering, going into off-limits areas or past safety barriers, etc.), get their good-tourist visa revoked. Interested countries like Iceland can then only allow people with this visa to travel there.