IMO breeds of dogs were created to serve a purpose. Responsible breeders make sure that thier lines produce dogs that serve that purpose. If everyone got dogs from a shelter and no one bred, what dogs would be used for hunting, hearding ect. Dogs work, and some are better at some jobs than others.
Adopting from a shelter is a great idea when looking for a companion animal but very rarely can they perform a specialzed job (there are cases where they have though!
And even if you adopt a shelter dog, you aren't saving all of them. Adopting from a shelter takes the same time, concidration and care as picking a breeder. You have to pick a dog that fits your situation. Blindly rescuing a dog could end up with the dog right back in the shelter, and often this is the case when people don't evaluate why they want a dog.
Responsiblity is the issue here, whether it be in breeding or in shelters. Shutting down breeders isn't going to make people any more responsible. Awareness of the issues are.

Edit: I just said basically the same thing you did, par lol.