We breed dogs so we get to sell them to people and make them happy. But we're "backyard breeders" so our adult dogs are members of our family and no, they're not for sale. They watch TV with us and sleep in our bed. (Not all on the same night or there'd be no room for us with eleven of them.)
My wife and I have had to live apart for economic reasons for several years, and one of the dogs I have here with me is the joy of my life. She's got the other nine in a huge house on five acres.
If by some bizarre twisted bad-movie plot, selling him to Bin Laden or an an overlord from Tau Ceti would bring about world peace, avert a meteor strike, or something like that, well then of course I would be a good World Citizen and make the sacrifice. But that's comparable to sacrificing my own life for the greater good. Sure, as a good swimmer I'd jump into a raging river to save a drowning baby, knowing that I might not be good enough to survive, much less save him. But I wouldn't do it for money.
But selling him just for the money? No way. Pets are members of the family who love you and trust you unconditionally. That's the whole point. We have to repay that love and trust, it's one of the things that makes us human. Anyone who would sell their dog just for the money, without an overriding reason such as an allergy or being about to go to prison for twenty years, is not someone I want in my community--or on my planet.