This rule hopefully will stop overfishing because there will be less fish for us people in the future.
Overfishing destroy all fish and other sea creatures and they will become endangered.
Another point is that, those people who are fishing are wasting fish that they don't want. They throw away the fish that they don't need and that is a waste.
Fishermen are also destroying the habitats of the fish by using all the new technology equipment like the 'wall of death' - or net of death.
The rule is also stop commercial wants because people who are fishing all they want is money. Charging $100,000 might stop all those fishermen from overfishing and doing it for money rather than just for food.