Well, some people have horror stories like finding out that the pet they got from Petsmart had a contagious disease and it spread to their other pets at home. Also, there are reports of Petsmart selling products that were actually harmful to pets. For instance, a certain brand of pet food was recalled later but Petsmart had been selling it for a while without proper warning. And then there are tales of pets being misplaced in the store and not being found for hours, causing great distress to the owners.
There was a story where a customer brought in their dog for grooming at Petsmart. When they picked up the dog, it had a large cut on its paw which wasn't there before. Apparently, during the grooming process, the groomer was careless with the tools. Another horror story is related to the adoption process. A family adopted a cat from Petsmart but later found out that the cat had a serious genetic disorder that wasn't disclosed. It cost them a lot of money in vet bills. There are also instances where Petsmart had issues with the cleanliness of their pet enclosures, which could potentially expose the pets to various diseases.
One horror story could be about a pet getting sick shortly after being bought from Petsmart due to pre - existing but undetected health issues. For example, a puppy might have had a parasite but it wasn't noticed during the check - up at Petsmart. Another could be a case where a pet was mistreated by an employee at the store, like a fish being dropped during a tank cleaning process. There are also stories of wrong medications being given to pets which led to adverse reactions.