I doubt that this is a problem peculiar to rotary pilots - I'm sure it happens with fixed wing too.
Many PPL(H) holders I've come across (I'm talking those who do not wish to persue a career in aviation) are well off and generally have managed to achieve this through taking risks in business. Helicopters to them are either a tool for getting for A to B or a means of leisure - they are not beyond taking a few risks/short cuts in either their business life or their time off. This inevitably results in a lowering of standards.
But they are not wholy to blame.
Ultimately a flying instructor has to teach the following:
1. Fly the aircraft
2. Pass the exams
3. Navigate and Communicate
4. Airmanship
The last one is the one that has no syllabus, but is just as important as the other 3. Airmanship is not so much learnt, rather etched into the student as an attitude. It comes from the experience and attitude of the instructor, based on the instructor's own training, experience AND attitude.
So who is to blame?
Sometimes the pilots themselves, who regardless of training will always fly the way they want to.
Sometimes the instructor for not instilling airmanship in their students.
Sometimes the chief pilot/chief instructor for not monitoring the quality of their instructors.
Sometimes the examiners for letting all of the above to get away with poor quality.
Doesn't matter how much experience (PPL, CPL or ATPL) you have, the moment a helicopter is strapped to your back, you cease to be anything other than a helicopter pilot - a professional helicopter pilot.