Honey, don't worry - I broke down crying and shaking in Walmart a few days ago. I complained several times, and was ignored every time, until I just lost it and demanded to speak to a manager. I stood over her while she cleaned the cups out.
I took 3 of them home with me, which I know is not ideal. I took one first, then went back for the two little girls after visiting and thinking about them for days, and seeing that no one wanted them. While it made all the difference in the world to these 3 little animals that I am in love with, I was making room for more on WM's shelf. I justified my actions by saying that WM would replace them if they died anyway, so either way, another fish would end up there; at least I saved one in the process.
What you can do instead is complain your rear off, and force them to care for the fish they are selling. Write to corporate 50 times if you have to. Call the manager a million times and complain if you have to. Take pictures.
I won't judge you or blame you if you rescue one of those little guys, and in fact you will be saving a life doing it. But don't think that you HAVE to buy them to help them, because you don't.
Thrilled to say that when I went to check up on Wally World's fish today, the Betta rack was EMPTY. :D
The only cure for ignorance is education, and bullying or attacking someone is no way to educate them.