Although I think the dispatcher was wrong to say it at that moment, I can see her point - the woman didn't even know what kind of dog she had? Hey, Jim, what sort of large predator did we buy for the kids to play with? Idiot.
On the other hand, any dog that goes for a baby's face should probably be put down. The owners are unlikely to want it and, frankly, why should it get to live when thousands of dogs who haven't bitten a child are being killed for lack of a home every day? Maybe it'd be worth it to rehab and rehome the dog if there wasn't such a surplus, but as things stand, I think it's wrong to spend time and money on a dog with that history.