By looking at the video and the eyes of the rodents I'd say that they have some kind of infection, bacteria or virus. I doubt very much that PetSmart breeds their own rodents. It's more likely that they buy them from some big rodent shop that breeds them, I'm guessing if it's in PetSmart its probably going through the whole rodent breeders colony. That's the door I would be knocking on next. It's not just a handful of rodents, it could be hundreds or thousands infected. I think that PetSmart needs to find another rodent supplier. Doesn't really seem to be the problem of the pet store unless they are not giving them food and water and clean bedding, they didn't say anything about those details. Personally if I owned the store I'd move those rodents to a separate room or building and mark them not for sale and in quarantine until they can be medicated or in extreme cases euthanized. I've had sick rodents in my colony, it happens and it's not fun.
The other thing that scares me is that a lot of rodent diseases can also affect humans and can be lethal. They should be wearing masks and gloves to move those sick rodents out of the main part of the store, better yet a separate room or building with HEPA ventilation to keep it contained.
It's crazy that they will confiscate rodents, but what would they say about feeding live rodents to baby snakes? Sometimes that is exactly what it takes to keep the snakes alive. It's a double edge sword and a fine line we are walking... I doubt very much that you can equate a rodent to a dog or cat. If you fed a dog or a cat to your snake you would probably end up in jail. However, it doesn't mean that you can mistreat rodents either.