I would be dreaming if I was to ask why teacher’s were not assessed as to their ability, but after all, it was the sixties and what went on behind closed school doors stayed there. To me, these Heads and senior teacher’s are nothing more than bullies. And paid bullies at that.
I say this because it comes across in your post that more times than not, “Punish first, ask questions later” was the practice.
Refusing to put your hand out was a rare thing at my school but it did happen, and after a while caught on like the Bell Bottom Pants craze. I know I have been in that position and the teacher’s were unable to do anything about it. At least you were given the oportunity to convey your side of events to the Headmaster, who after listening to both sides of the story would simply send you back to class. No punishment was awarded.