Not all...Most But Not All
Here in Puerto Rico, where the situation with dogs are very bad, I have found a few pet shops that in my mind are awsome.
1) Pet Shop A; This is a very small scale pet shop owned by a vet. He sells your typical pet shop stuff: Food, Collars, Shampoos, etc. BUT he also vaccinates your pets for the cost of the vaccination, maybe a tad bit more. He is also willing to check your odg for a very low fee and give u something to treat your dog that if its possible, fits your budget.
Pet Shop B: This one also sells your typical pet shop things, with one exception: He sells puppy. But I can guarantee you these are not puppy mill pups. He is a small scale breeder, specializing in Great Danes and Labs. All his pups are AKC registered, and parents are thoroughly tested. He does not carry dogs from other breeders, but he does post up flyers in the shop, but only if Pups are registered, healthy and parents are also healthy and available to see.
Every once in a while he gives these 'workshops' educating people on so called dangerous breeds, his main goal is for people to see that there are no bad dogs, just bad owners.
While most shops are bad, there is always 1 or two gems in the group