Our PetCo is crap here, and we just had a PetSmart open that seems to be doing things nicely. I have sold some of my normals to pet stores ( locally owned ) and I always go over the proper care with them, plus check out their current setups and how the animals look before even offering my snakes to them.
Not all PetCo and PetSmart stores are crappy, but I definitely prefer to buy from breeders.