bullying and abuse
There is an excellent article on this 'abuse' thing written by Ellis Amdur, in his book Duelling with O Sensei. He talks about being treated very badly by a senior aikidoka, within the ear and eyesight of the instructor (who I seem to recall was K. Ueshiba) and it was allowed to happen. He explains a lot about the difference in culture between Japan and the US and how this influences this type of behaviour.
I took away the impression from his writtings that the kind of behaviour being discussed here is considered more acceptable/the norm in the Japanese culture and is present throught the school system, with society handling it in a very different way to how a westerner would expect.
Very interesting stuff. Get the book - you won't be disappointed.