in the town where i grew up, there were a couple of fairly large breeders. . .this was back in the day, before people even knew what pitbulls were. . .at the time they weren't even recognized as a legitimate breed by the akc. . .these people lived out in the sticks and pretty much minded their own business so, even though people knew what they were up to, no one ever bothered them. . .plus these people were bad-asses. . .not the kind of people that you went out of your way to fuck with.
anyway, due to the breeders in the area, there were always a lot of pitbulls around town. . .unlike vick and his boys (and probably a lot of other breeders), these guys took their non-aggressive dogs and just gave them away to people that turned them into pets. . .generally speaking, a little non-aggressive 45lb female pitbull can make a pretty decent pet. . .they're very playful, intelligent and extremely loyal. . .however, the males (for the most part they kept the males for fighting purposes) that were large and aggressive, after they had been trained as pit dogs, were pretty much useless as pets. . .even though these guys were extremely "humane" (as humane as a dog-fighter can be) by today's standards, the trained dogs were pretty dangerous. . .they were extremely aggressive, they weighed around 100lbs, they were solid muscle and they didn't know fear. . .even if they were being chewed to pieces, they did not surrender or show their belly. . .these dogs are very game and even though the "sport" (for want of a better term) is gruesome and despicable, there is something beautiful, pure and mystical about a being that will willingly fight to the death.
as far as what they were "born to do", that's kind of debatable. . .wolves were "born to" track down, kill and eat caribou. . .the american staffordshire (pit) bull terrier is a product of selective cross-breeding to develop a dog that possessed specific genetic qualities. . .fighting is what they were "bred to do". . .