That, sadly, may be true. But one cannot save fish by buying them because cash flow generates an interest opposite of what we'd desire.
I'd think we desire both vendors and buyers to become aware of what they are doing, to learn a lesson. When either or both suffer losses, a little bit of pain, they (generally) learn, sadly but true. When either or both pass along their problems to someone else and get some or all of their invested money back, or even a profit (!), it only encourages the inhumane practices they had already become a part of. A vivid propagation of a proverbial vicious cycle.
For the third time, sadly, we tend to learn the best from our own actions and their consequences, not from reading about actions and consequences of other people, nor from general education or awareness or advices of others.
We tend to think highly of ourselves and reckon, even if subconsciously "This will never happen to me, I got it under control, I'll find a way, I... I... I..." Or not think at all, just engage in as much daily pleasing of ourselves as we possibly can - that is the other prominent reason, namely, that we tend to be selfish and strive to please ourselves first and foremost "I want this fish. I am getting it." Instant gratification.
We forget or learn later that any commitment, be it to a human being or an animal, is both a pleasure and a sacrifice. We all know and like the first part. We don't think about the second part but it will never go away. And in the end, it is the other party in our commitment that pays the ultimate sacrifice. Our "beloved" pet.