What Daryl said is right. I will preferace (sp?) my comments by saying that I am currently on the committee of our local Hobie Association.
In Australia we are lucky to have forged a strong working relationship with the factory by means of sponsorship, prizes and logistical support to all of the local associations.
In order to build this relationship the local associations are spending significant effort in developing hobie cat regattas beyond the standard state and national titles. One such series has been the highly successful travellers series in NSW.
Without the factory's support, these sorts of things just wouldn't happen. To expect continued support by allowing other boats to compete is living in fairy land.
The factory won't stop anybody from competing in open regattas but they won't tip money into anything but their own class. (How many other manufacturers do?)
HC(Australia) make no appologies for this and I have to say that I agree.