In the last 12 months, I have probably flown over (through) AV about 20 odd times at different times of the day.
In all cases I have made the recommended broadcasts and, to the best of my memory, I have only ever presented a traffic confliction once to any other aircraft.
The rest of the time, the silence has been golden. I certainly wouldn't think that AV even warrants CA/GRS - let alone a tower!