Besides, where are "your" waters? Why do you use British licensing to have something to do with "your" waters?
British waters are public. Your waters are yours.
Public means that everybody in Britain can use them. Why is it that government needs to get paid (licensing) for people using what belongs to them?

For the same reason why forests that are public also are not public.
You can walk into a public forest and, gather herbs and mushrooms, but you need a license to hunt and cut trees. What is available to the public is in reality very limited. In most countries you need a license to fish in lakes and rivers, to sail, to put a water wheel in and make your own electricity. Public means you can go there and watch, that's it
