If it is not a dog, it is a SUV.
Or a dog driving an SUV.
SUV's don't have teeth and don't spontaneously start themselves up, leap out of locked houses through living room windows and maul passersby.
If it seems reasonable to own a rottweiler as a pet, especially a 150 lbs. rottweiler, then it should seem just as reasonable when I shoot it and claim it tried to attack me or my child.
The chances of people believing me are going to be a lot better than me making that claim about your SUV.
Either chain them to something solid, or don't get upset when I come kill it out in your driveway.