How do you convince the New Zealand government to ban Shark fishing?
Just create a reason for New Zealanders to voice their opinion.

Greenpeace wanted to make New Zealanders aware that their government still allows shark fishing in their waters. Sharks are hunted by Japanese fishermen for their fins to make shark fin soup. Lets use those annoying internet trolls to drive home the message to the Kiwi government. We launched a brand of New Zealand shark fin soup, fed it to the trolls and waited for the public anger to pour in.