Tolerance is part of the issue
Good read, we have dealt with the not calling hits, by the fire at centre of mass, if you see bb's hit and they do not call shoot them in the legs. Most people will feel that hit. Worst case walk to them ID, them and report them to the game organizer. To be dealt with by the game organizer.
BUT you must have seen the bb's actually hit the target.
How does that relate to tolerance, well back when our field had 12 players as a big game we were a little more tolerant and gave more time for bad behavior / attitude to be corrected.
Now averaging 50 to 60 players per game, we are actually less tolerant, we don't need giant egos and small dicks ruining the day for everyone. So one warning, a second issue then see you, in addition we report to the other local clubs. We make it very clear in the pre-game speech this is how it works.
Oddly enough the biggest trouble makers don't show up anymore.
But a demo for new and old players of the inherent lack of accuracy of the average AEG helps. We fire a 10 round burst a pie plate at mid range, in the clear taking all the time in world to aim. Then do the same with the plate in the brush doing a quick shoulder and burst.
The results sober up the guys who think they never miss. We have had a few cases where no rounds hit the plate the obscured plate.