I dont believe that the large percentage of breeders out there who have their litters docked are cruel, I think they love their pets and just do what they think is right by their pets.
However there is a small minority of people who do not do tail docking the right way and the pups suffer it is these people who should be targeted and held accountable by law.

My friend went to see a litter of rotties and they were not in a very good way and their stumps were infected she reported them and the pups were confiscated but they did not face charges as there was not enough evidence and they are still breeding.