Yes, back when I was showing and breeding we did sell the puppies to carefully screened homes. But for all responsible breeders it is very different than the idea of an investment. In our circle you don't get to have a puppy from one of us just because you have the money to buy one. I'm not sure if it is like that with horses.
My process and just about everyone I know, required an application online and if I liked what I saw then a phone interview. If the phone interview was good then everyone in the prospective family had to come and meet me and the 4 legged crew. If that went well, then we could proceed with a deposit and go over the 5 page contract that detailed their and my obligations and responsibilities with regards to the welfare and care of their new furry family member, aka, my grandpuppy. Show quality puppies were kept by me or placed with qualified show homes that had good referrals. This all took place before the puppies were born and I turned away many more families than I would allow to get on a waiting list. The puppies were my responsibility for life and always have a home with me, no questions asked, if circumstances for their new family changed. As a responsible breeder, I was also obligated to be there for those families whenever they needed support, advice on health, nutrition, training etc. I don't get to walk away from that the way I would if it was a car I sold. When the day eventually comes that they are faced with saying goodbye to the dog that has brought them joy and wonderful memories, grew up with their children has now crossed the rainbow bridge and left a gaping hole in their lives they are heart broken, then I'm the one they call. They need to be able to cry and reminisce with someone who understands, it's not "just a dog."
I think it's a lot more personal with showing dogs than it is with horses. It's definitely not an investment. I wish. Dog sowing and responsible breeding is a money pit. I was lucky to break even most years. There were some that I never could or would place because they had a firm grasp of my heart and soul. Two of them were Golden Retrievers and one was a Cavalier King Charles Spaniel. I also showed and bred Cavaliers briefly but couldn't do proper justice splitting my time and effort in two breeds so I stuck with Goldens.