Blowboaters.
The club I was in did not converse on 16 but monitored 16 unless they wanted to converse and then did a very brief request for others to join them on another channel. It did result in more boats monitoring the channel but it also meant that there was a tiny chance that someone trying to get help would have to wait a few seconds because a conversation request was being made. I am not sure whether the benefit of having more boats monitoring the channel outweighs the potential for that causing a problem or not. I also noticed a lot of other people did the same thing, hailing a particular vessel or anyone in a particular area and asking them to go another channel. I honestly don't know what makes more sense. In an emergency, it would be nice if the other boats nearby were monitoring 16.
I know in some places the kayakers chat on 69, but they aren't likely to be able to help with a power boat's distress call anyway.
Do the regs explicitly say to never make a non emergency transmission on 16?
EDIT - looked it up quickly to answer my own question. 16 is for "
Distress, safety and calling" and I believe that what the club did is "calling".
Channel Frequencies and Usages are from the Coast Pilot; Pacific Coast (25th Edition)
CHANNEL
TRANSMIT/RECEIVE (MHz)
USAGE
----------------------------------------------------------------
16
156.800
/
156.800
Distress, safety and calling