I have to admit, my PetSmart isn't bad. I like it better than the Petco that is closest to me. I wish they'd set up a real crab tank for their crabs and frogs, but the fish staff there have always been as knowledgable and as pleasant as at any of the pet stores in the area (which is not saying a lot, but it's better than being worse).
I buy my tanks used and most of my supplies online, but I have been known to buy fish at PetSmart. None have died suddenly or unexpectedly, or even gotten sick that I can recall. Most of my fish have come from there, now that I think of it. They just seem to carry a better selection than the others I have to choose from.
If it weren't for them, I'd have to patronize either a full service pet shop (dogs, cats, birds, the works), or a decent store (no dogs, and only rescued kittens) that nonetheless carries dyed tetras and seldom has fish I want. I've heard on this forum recently that there are two good places within an hour of my house, but I usually prefer to stay local so they aren't in the bags too long.
Anyway, I sympathize with your good intentions, Fish Guru, but it seems to me (judging from the responses here) that PetSmart is doing a pretty good job, considering it's a humongous chain store, and those of you who have had bad experiences might consider petitioning your individual stores for care that is more in line with the chain as a whole. Perhaps you can send the store number or location to this Dr. Nick Saint-Erne fellow at PetSmart Headquarters and they might reprimand the store?
I would wholehearted support a petition to get the aquarium trade out of W*mart stores, however. I think I signed one once already. You hear of the occasional WM that takes good care of its fish, but it is definitely the exception, not the rule, and seems to have more to do with a particular employee than with the store itself or the company. WMs around here are all shabby and poorly run in my opinion, and I wouldn't cry if they all closed their doors.
That's my 2 cents.