In my experience we had more problems of that ilk with PE staff than anyone else. I suspect it was because their gym was their domain in their eyes. Many I also guess felt inadequate in the academic environs of the rest of the school. (prof n.)
PE teachers did seem to have something of a reputation for being “slipper happy.”(Jenny)
Far be it from me to defend bullying PE teachers, but the purpose of these lessons was not just about physical fitness but learning self discipline, team playing and, to some degree, personal presentation and hygiene.
I believe immediate correction for stepping out of line may have had a useful part to play here. And as Voltaire might have put it, the dramatic effect served “to encourage the others”.