No, mug is the wrong word!
As a professional groomer, I was always worried when one of my clients bought a new puppy. If I knew that was what they were going to do, then I would try to steer them in the right direction but most families buy a new puppy every 15 or so years and have no idea how the world of dogs and dog breeding has changed over the past 50 years.
In those days (I'm nearly old enough to remember!

) dog breeders were passionate enthuiasts, usually wealthy people with plenty of space to keep many, many dogs, as it was not as easy to travel as it is these days. If the average family
had a dog, it was a mongrel from the lady up the road because her bitch got out!!
These days, the breed enthusiasts are still around, trying to maintain the quality of the breed, testing for any hereditary problems that have come to light, and sincerely doing their best to breed happy, healthy pups, considering themselves custodians of their chosen breed to pass on to the next generation. A caring breeder will be concerned about where her pups are going to live, ask loads of questions, keep in touch with the new owners, and provide back-up from their many years of experience should the pup or new owners experience any problems.
Unfortunately there are now people who see producing puppies as a means to making a fast buck! They have no health tests done on their breeding stock, keep them in poor conditions, breed from their bitches every season (one reason why pups are not registered!) and use cheap food etc so that they can make maximum profit. They breed any pedigree dog to any pedigree bitch with no knowledge of genetics to know what they might produce, have no experience to pass on to the new owners, do not care where their pups will go, and so long as you can pay the money asked, then you can have a puppy!
Those of us who have worked with dogs have spent many hours doing our best to help and sharing the grief of those usually lovely families who have bought from such a puppy producer in complete ignorance.
Many of the posters on this board are very involved with their chosen breeds and care deeply about the future of them. Maybe this begins to explain why the requests for mating a pet bitch or offering a pet dog at stud is sometimes answered with short shrift!
So you see, you're not a mug. I'm sure that I would know nothing about your passion in life!!
PS Your Vet is like you GP - OK for general things. But eyes have to be tested by a Veterinary Opthalmologist, and as there aren't that many in the country, the chances of your Vet being one is quite remote! He would have certainly charged you extra for his professional services if he was!