Yep stupidity.
I assume this is just how life goes, but over time on the water things have generally changed for the worse.
Boats drifting in places where years ago you never would have gotten away with it.
Boats anchored in places where years ago you never would have gotten away with it.
Even on the beach, people showing up and trying to soak 2 rods worth of baits in places that everyone fishes with artificials - years ago nobody would have let it go on.
Basically, these unwritten rules allow everyone to get along, to fish around each other successfully. Lots of boats can anchor or drift an area in unison, up until one decides to do it differently.