Well, their isn't really a dog 'population' problem. There is a 'stupid people' problem. The shelters aren't full because their are more dogs than their are homes... the shelters are full because of people who buy or adopt, then either the dog 'runs away' or they abandon it, or they stupidly allow their dogs to breed unwanted litters, or breed mutts that are 'cute' and nobody wants... off to the shelter. Real breeders breed because people buy. If their were waaaayyy to many dogs, nobody would buy, so the breeders would go out of business and stop breeding, then the shelters would be all mutts. :shrug: Not that there is anything wrong with a mutt.
Plenty of homes out there for dogs... its just most want the dog they want, not someone elses cast off. Sad, but true, and personally I don't limit myself to what others have thrown away either... It just happens that I've been lucky enough to find what I want at the shelter.