This quote is about AMstaffs which were breed for that same thing as pitts and are quite similar....
Although the early ancestors of this breed came from England, the development of the American Staffordshire Terrier is the story of a truly American breed. This type of dog was instrumental in the success of farmers and settlers who developed this country. They were used for general farm work, hunting wild pigs, bears, and other large game, guarding the homestead, and general companionship.
A number of the early ancestors were also developed for the "sport" of dog fighting. The extraordinary vitality of this breed is a direct result of breeding for successful fighting dogs. This now illegal activity is, unfortunately, more often cited as the early purpose of the dogs rather than the general farm work.