I totally get where everyone is coming from. The only thing is, while we are refusing to buy the fish, they suffer and die. And will continue to suffer and die because people won't stop buying fish, or any other pet. The choice is a hard one, and I agree paying the people who mistreat the animals will only encourage what they're doing. But the alternative is not great either, just letting the animals either die of illness at the store or going to a home with people who consider it a decoration, or "just a fish". It's an almost impossible choice.
Kindness and respect should be shown to all animals, no matter if they are furry, scaly, big, or small. Be a hero to the animals and GO VEGAN!