Well, there it is: “harboring a vicious animal.” You see why such dogs are so well liked by people with criminal minds now. It’s a way of getting away with murder.
It's more like that such people are felons, and cannot legally possess a firearm. Particularly drug dealers.
Ergo, if you're of the criminal mind to begin with, chances are that something's going to happen to bring LEOs in, and not having a proscribed weapon around is beneficial.
Pit bulls act as deterrents to casual snoops, as well as adversarial acquaintances trying to poach action and/or ripoff stashes and swag.