A body of water that is not fully on a golf course and is part of a larger body, such as a lake, ocean, river or pond should not be overlayed with a duplicate water layer tagged as a water hazard purely for a golf game.

To map something temporarily is wrong and is against the guidelines.

Trust me, I share Allison's frustration with Golf Mappers and the vandalism.  I have spent the past few months having to police and clean up after golf mappers who have done some wild things, some even doing significant damage to the map.  The efforts of volunteers could be better spent supporting humanitarian projects, like mapping areas that were impacted by the recent tornadoes.  Being able to assist in search and rescue and surveying is a better use than cleaning up after people mapping for a golf game that can't import certain features so users must intentionally tag things incorrectly.

Actually, the volunteers are kinda sick of it. Some users have resorted to just reverting things generously, regardless of whether some of the changes were valid.  There is just enough time to sort through all the golf edits, especially when many are incorrectly deleting and readding features already, which goes against other OSM guidelines.