This is a situation where you need to be careful not to speak in absolutes. There is tension between some Korean and some non-Korean Masters and there is a couple of reasons for this.
1. It was not unususal for Korean Masters to take advantage of naive round eye students... charge excessive fees, delay rank advancement etc. When the round eyes woke up they were P.O.'d
2. Some Korean Masters, particularly newer ones hate to admit that any round eye might actualy know more than them having trained longer with better instructors. It threatens their superiority complex.