People are taking the free animals and using them for baiting in dog fighting rings or if they are purebred and no neutered they are using them in backyard puppy mills.
Animal abuse is running rampant in this country and by providing abusers "free animals" you are subjecting that animal to torture and ulimately death.
Though craigslist states that it warns posters about the potential for animal abuse and asks them to go to the "free homes for good pets", they rarely do. Generally the animal is picked up by the person who is getting the animal.
There has been a recent high profile case in Houston, Texas where a couple was making CRUSH films with dogs off craigslist and other classified sites that offer free animals. See video.
Should this really be the way we allow our animals to be trafficked?
CRAIGLIST .. DON'T BE PART OF THE PROBLEM, BE PART OF THE SOLUTION.