Same here in Australia.... also very usefull when we get rescue dogs as some are returned to the good Breeders or at least we know their history and who owned them. So we can keep a list of where they should never go again. Or from which Breeders a lot of rescues come.
In my opinion, it makes sense to have the breeder chip or tattoo the pups so they can be easily traced back to the breeder as was noted above by R Taft. Even in the show ring...what is the safeguard that the dog I bring into the show ring is the dog I say it is from XYZ breeder?