Yup, Walmart is pretty terrible with fish. That's where Odysseus, my first betta came from, knowing what I do now though about how fish should be properly taken care of, I don't know that I would get one from there again. I know I'm not going to make much of a difference, not buying there myself, but still. It's the principle of the matter. I've gone to the Walmart nearest me and seen dead fish floating, dead fish on the floor, just dead, dead, dead. Or suffering. Immensely.
However, that being said, I would not give Odysseus up for the world. I just wish he hadn't been placed in the position where I had to rescue him in the first place.