One time I ate shrimp, even though shrimp farming and fishing are oftentimes one of the most environmentally destructive things humans do to the sea, between bottom trawling pollution, fishing pollution, salination of the water and soil, destruction of mangrove forests (extremely vital to the ecosystems and preventing erosion), and greatly depleting important biomass in the oceans to potentially unrecoverable levels.

It's bad for the environment, and it's bad for the 1/3rd of the world who rely on fish products for their animal protein.