Kinda weird how here in the UK (or at least where I am) we don't have anything like this, maybe even the opposite. I mean there is 'pets at home' which I guess is a big chain store also but they have not bad stocking and the employees are extremly knowlegable (spelling?). Ok, when I went the last time they had dwarf puffers in with firemouth cichlids and jewel cichlids in with bumblebee catfish, which wasn't good as there wasn't any puffers or catfish to be seen... but they quarantine the fish when they arrive, and you have to fill in a form about the specs of your tank. so I guess you have to commend them for that. The reason I am saying that its the opposite is because the two stores in my area that only concentrate on fish are terrible. The first one doesn't even have the names of the fish just 'this tank "£3"' etc. Its not disease full in every tank but they just have the odd single tetra here and there. I did buy a guppy from there which ended having fin rot and died a few weeks after buying it, and I wasn't too happy cause it was really pretty...
The other store is just diease full in every tank, the angelfish have practically no fins and are basically circles, its basically just pretty rubbish :/