When is a workplace, not a workplace

On 20 February 2017, WorkSafe Victoria issued a media statement about several recent fatalities.  Below is the first couple of paragraphs with some highlighted text:

“Two men were killed and another suffered critical head injuries in three separate incidents at the weekend.
On Saturday, a man in his late 30s died when his quad bike overturned on a property at Reedy Flat, near Ensay, in east Gippsland. It has not yet been determined if the property is a workplace or a hobby farm.” (emphasis added)

Why was the status of the farm mentioned and how is this relevant?