Shouldn't a student adapt to the dojo environment or leave if he/she does not wish to? New students should check out a dojo before joining, if they see that corporal punishment is accepted there and they don't feel comfortable with it then they can either not join, or they could speak with the sensei about their feelings on the matter. Really you need to adapt to the culture of the dojo not expect it to be the other way around.
Replace "dojo" with "workplace", change "sensei" for "sexually harassing boss" and would the conclusion still be the student (worker) must adapt to the culture?
I think I understand the point you're making, and admittedly I'm extending your statement past what you no doubt intended. I guess I'm trying to express that there is some behavior that is inappopriate, despite specific cultural considerations. Physical abuse would be one such example, at least to me.