Show breeders more than any other have ruined working dogs and other dogs by selecting for these traits that win at dog shows by line breeding to those traits that win and to winning sires that exemplify the winning model. Exaggerations, popular sire syndrome and genetic poverty creep in until the dogs is a wreck of a breed. They have to be bred in closed registries to get pedigree papers, to enter shows. 

"Pet breeders" or what ever you want to call them do nothing of the sort. They aren't showing their dogs. Do they care if the stop of the nose is slight or deep? No they don't. Do they care if there is a little bit more white on the chest than the standard dictates, no they don't. Are they line breeding for exaggerations in phenotype, no, to winning sires, no they re not..............They don't turn the breed into a parody of itself, they don't have incentive to do this like show breeders.

Look what has happened to the Rottweiler, it's face looks like a bus hit it, like it was morphed in photo-shop. A pug on long legs. This happened in the show ring no where else.

Would I buy a Teckel from a show breeder? Absolutely not. I would find a breeder who was selecting and breeding for working Teckles. These don't have extremely long diseased and accident prone backs of the show dog, these don't have tiny useless bent legs like a show dog, these would still have drive these would still be able to work and function as a dog as a working animal and a pet. They don't have mental health issues associated with inbreeding, they're athletic and live a long HEALTHY life. As a pet owner I would do the same just because I didn't want to end up with a disease riddled drain on my bank account and heart animal. Would I want a great big lump of couch-potato riddled with disease and dead at five like a show Mastiff, no I wouldn't why would anyone? Such a dog is not even athletic enough to be a pet. However those exact exaggerations that make it so useless for anything make it a winner in the show ring! Its not rocket science just bad breeding. 

Unfortunately pure companion breeds are not immune either. A show bred English bulldog, pekingese or pug cannot walk even a hundred meters in the sunshine in Nordic Scandinavia without turning blue and showing dangerous signs of asphyxiation. Did "pet breeders" do that to them no. They have been bred for the show ring for ever flatter faces with nasal passages so compressed they cannot breath due to large lumps of folded flesh in their air ways, and thats just one problem amongst many they have............

It is an irony, yes absolutely but you are more likely to find healthier animals sold in a pet shop without a pedigree! That doesn't mean I agree with puppy mills.....or disagree with pedigree dogs per se either. A pedigree is just a record of ancestors not a seal of quality and the more show winners in it the more likely you are to get a dud.