It adds nothing to the game, it's not a fun or interesting mechanic, it's just an additional annoyance and then they de-spawn once you get close enough to snipe them.
All that does is force you to park closer to the island - rather than being able to stop further out and then launch over with a canon - otherwise your ship gets shot up.
Giving us minutes of repair time without combat when we try to visit any large island is not my idea of a good time, more like a waste of time, only forts should have them.
