I believe the so called breeders they use are either back yard breeders, brokers, or puppy mills. Cannot track the breeder of the puppy I purchased  there other than at website -PetShopPuppies where I found the breeder who seems to be a broker and/or puppymill.  Had I known this, I would not have purchased my puppy thru puppy stop and gone directly to a reputable breeder.  Purchasing puppies thru a petstore just purpetuates the broker and puppymill horrors that these poor dogs must live thru.
Cons:  A legitimate breeder will not sell a puppy to a pet store
                        
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