A better question is why the Animal Rightist want ear cropping and tail docking banned.
To which the best answer dog specialist have come by is that Animal Rightists are in FACT againts the ownership of companion animals. Wayne Pacelle says "one generation and out"..." we have no obligation to preserve domestic animals." Read that to mean once they are ALL spayed and castrated there will be no more born. Why, one might ask; is because dogs eat meat. In other words why should we have a companion animal that uses other animals for food when animal rightist, who run organizations like HSUS and Peta, are Vegans who not only do not eat animals, (nor milk or honey) but also do not wear silk or wool.
So now back to the original question at hand:
Once tail docking and ear cropping are banned breeds will be less recognizable. they will be less apt to entice people into wanting them. Further, while all this goes on, Peta and HSUS enjoy a banter of badmouthing people who actually care for dogs - the breeders. Meanwhile they also enjoy support from the sub groups of shelters which IMPORT dogs from off shore like the North Shore Animal League and several in California and across the US. Whilst they SELL these imported dogs for between 150 and 250. The goal to stop all breeding and eventually end all dog ownership. Baby steps such as banning tail docking only serve to hasten their end goal - NO dogs or cats (which BTW need taurine and must eat meat).
Call it socialized communism if you like because it is an end to FREEDOM OF CHOICE.
Amazing that people can pierce a baby's ears for earings (although that may be illegal for a guardian of a child to do) and get no flack but crop an ear or dock a tail and society wants to jump and shout.
Why? Because the vegans - with an agenda - have society all reiled up. The truth is they want to END dog companionship.
ADD 2: People please think. Are the tails of all breeds the same in their natural state? Is the tail of a Doberman which is thin more likely to sustain damage than that of a German Shepherd Dog? Not only do breeds have different qualities and susceptibilities in their tails but it becomes even more dramatic when discussing individual lines or dogs themselves. It always amazed me why we as a society assume that we know of what we speak when experience limits us to a given set of circumstances. Not all breeds are the same. There are many non docked breeds like sight hounds which sustain quite a few breaks. If sight hounds had the temperaments of sporting or working dogs they would surely see an ER for tail docking as adults in high percentages. Why individuals within society assume a supportive position on topics they know little about without observing the underlying objectives of the position's proponents I do not understand. People with limited canine experience assume a one size fits all rule should apply to all canines simply because a good argument is heard without considering all the facts and circumstances within given breeds. Think and get some hand on experience before passing laws which will make dog ownership less enjoyable, and dogs suffer adult tail damage and ear infections.
ADD: Terrier you are correct. However the major players in the groups that are trying to sway legislation both in Europe and the United states make them Vegan organizations. In fact the largest of these groups promotes Veganism to the ranks of their organizations and even hosts of talk shows they appear on. (LOL if it were not for a weight problem swaying Oprah would have taken quite a bit more.) That does not mean that ALL Vegans are extremist to the point of creating Political Action Committees or joining Peta in campaigns. In fact some do enjoy having pets although it would be more than extremely rare to find a Vegan that allowed their pet to reproduce. That said, simply the fact that the common denominator of these powerful political groups is that they are Vegan plainly shows that they are extremists and do not represent the moral positions of main stream society. However these groups do not tell people that they are Political Action Committees (PACs) when they collect funds. The public assumes that donations are used to help animals while they are NOT. Donations are used for advertising and political goals, which do NOT necessarily represent what the donors believe. It is high time that the public becomes aware of what their money is being used for.