Not necessarily.
I know a few people who breed dogs that from breeds that are on the list of "native" (ie, British or Irish) breeds at risk of dying out. They breed them because they love the breed and they don't want that breed's unique characteristics to be lost. And I don't blame them, to be honest. The world would be a sadder place without (eg) otterhounds or Glen of Imaal terriers imo.
Then you have the "show breeders", who want to breed the best possible example of their chosen breed. Sadly, some of them take this too far and breed for exaggerated characteristics to the point that the health of the dog is adversely affected (yes, bulldog breeders - I'm looking at you!).
And some people breed working breeds with a view to improving their working ability, because they work them themselves. They will generally breed a litter every few years, keep the one they consider to have the best potential, and most of their puppies will go to other working homes. A guy who used to live near me bred a few litters of outstanding working springers, and he would never sell a puppy that wasn't going to a working home.
But the sort of breeder that churns out litter after litter of whatever breed is currently fashionable, or "designer mongrels", are generally only in it for the money imo, and are little better than puppy farmers.