I've seen a gorgeous pastel and stunning pinstripe at petco... but that was the one I worked at, that is now understaffed with only a single knowledgeable employee left. Even just the difference of 1 or 2 good employees can make or break a store. That said, petco has absolutely no say in the animals they order as far as quality of the morph is concerned. They order a snake from the vendor, and hope it comes in healthy. If there is a big enough issue with it, the animal can be sent back, but if it gets sent to a store with clueless employees, how willthey know what to look for? If it gets sent to a store with caring and knowledgeable employees, they'll set up the animal in quarantine like they're supposed to, go to a vet (if there is even a qualified vet in the area-- the area where I am at is extrememly limited and only for very basic procedures).

Not trying to defend chain pet stores, there are things I don't agree with about them either... but there are lots of factors at play.