They must be saleable breeds. Not heard of this in Britain, but in France.
There they have had puppies being brought in from Eastern Europe. These are bred in puppy farms , provided with fake pedigrees and papers, and passed off in France as bred by a breeder.
France is not like here. There you see adverts in newspapers listing lots of breeds which the advertiser has available, and large pet supermarkets which always have puppies from at least half a dozen breeds, on sale at any one time. You always now what breeds are fashionable; and dogs are very much a fashion item there; from the changing lists. So there have been fads for shar-pei, whippets,shi-tzu, and so on, changing from year . And the Eastern Europe farmers meet the demand for whatever breed is this year's fashion.