It all depends on what's happening on a given day.
Stations have so many crews out and so many story-slots to fill.
On a slow news day, they will take stuff they normally would not pay attention to.
And they'll drive further.
In addition, they do make a point to hit the outlying counties just so people don't think they are being ignored (and another station does not get an opportunity to claim they cover that area and the others don't).
One other factor, maybe channel 7 was there and getting good pictures, so channel 6 asked for a feed.