Most parents are utterly incapable of making an informed choice of music teacher, as they do not have the required training to evaluate such a thing. The only way to prevent unqualified individuals from undercutting the price of trained professionals is by a code of ethics that disallows "poaching" of students. This code of ethics has been a part of pedagogical history for hundreds of years, and lays the foundation for teachers being able to send students to the best possible instructor in the area without fear of losing their own client base. Without that security, teachers will hang on to their students rather than send them to an appropriately gifted colleague, will have to lower their rates to compete with unqualified freelancers, and the consumer will eventually lose out as they will no longer have an assuredly honest opinion of which teacher is best for their student, nor any way of determining the quality of instruction they are receiving. In addition to this, the number of qualified instructors will diminish over time (who wants to spend 20 years learning to teach the piano and have to compete with some idiot who can play passably well, can't teach, but has a silver tongue?) and the art itself will slowly disappear from American culture. It is absolutely embarrassing to think that America's own laws would jeopardize our status as a world leader in the arts. This code of ethics does not discourage competition amongst qualified teachers, as the organization frequently puts members' students up for public evaluation / performance, and clients are free to switch teachers as they desire. To reiterate, the security provided by the code allows honesty and goodwill amongst members in order to connect each student with the best teacher for them.