Hi Roz,
That's a good question, but I want to make a destinction here. If my mate next door has ever owned a boat, he is likely to feel a little sorry for me and the expense he understands comes with the territory of owning a boat. As a gesture of respect, he might offer a token sum of money for the pleasure of having fresh fish. I would not say no in this circumstance. But an unlicensed (not a professional liscense) amateur who deliberately catches more fish than he and a few friends could consume , knowing that he has a few people who willingly pay him money, and hopes to make a profit - I think that is wrong. The pros spend enough on their livelyhood without the erosion of their industry by privateers.
Scalem