Someone asked the same question yesterday.
http://www.yorkietalk.com/forums/gen...e-yorkies.html, Many of us think they are adorable, but don't believe that breeders should purposefully breed for them. There's a reason why purebreds have a standard, although many people don't understand this notion. If breeders don't follow the standard, the resulting offspring, will no longer look like the original breed at all, while this doesn't bother some people, many of us would like to only support breeders who care that a yorkie will still look like a yorkie in the future. Nothing wrong with buying a chocolate, but I would not buy one from a breeder who purposely bred for the chocolate.