Maybe if pet stores stopped buying from puppy mills, this wouldn't even be a topic for discussion.
Buying A Puppy : The Humane Society of the United States
In 1979, I bought a Cocker Spaniel puppy from a pet store at a mall because he was so adorable and spaniels had been my family's choice of dog for many years. He was all ears, cute and wiggly, of course. The store gave me a piece of paper saying he had had all his puppy shots and came from good, healthy stock so I shouldn't worry about any genetic problem. I'd had the dog for only 3 months when one of his hips slipped out of its socket (dysplasia), which IS a genetic problem. Of course the pet store said they would "replace" him at no charge (like you'd "replace" a pet rock). I wound up paying $500 for the operation, but the dog never walked correctly from then on. He finally developed arthritis in both hips so bad that he had to be carried, which is when I had to have him put down.