I don't know how you plan to sell your stuff. Are you going to sell direct only? Or do you plan to sell to shops? Or a mixture of both?
Just like now. If I can't get the stuff I want from shops, for whatever reason, I will buy from elsewhere, but shops would be my preference.
Chimera, it will cause no marine shops to close, because to my knowledge there are no exclusively marine shops in NZ, like you said, they would have closed quickly. Why is this? Simple, the market is too small to sustain it. But this may cause some shops to close their marine section altogether, reducing the public profile of the hobby. Like I have said in previous post in this thread.
Layton