Often people buy a puppy without knowing where it came from and beleive the pet shop owner when they say it is from a reputable breeder. Check out this webpage Buying a Puppy - Rescue a Dog and watch the video link.
We rescued a female Rottweiler that was in a puppy mill and was used to make money from her pups. She was kept in a small concrete pen, with no attentions and was overbred. She was ceased by a council raid in western sydney as 1 or 18 dogs in varying states of health.
These puppy factories supply pet shops with dogs, so buying a puppy from a pet shop supports keeping adult dogs in porr often inhumane conditions.
Hundreds of thosands of dogs and cats are put down every year becasue they cannot find a home. Why not Resce a dog instead?