All ADT does is call the police. During the most recent civil unrest incidents the police were not responding to 911 calls like this, making it pretty useless when you actually need it.
Police don't really respond to alarm calls anyways. The high degree of false alarms generally puts responding to these at the bottom of the list of things to respond to.
In a city. In a wealthy suburban community the police are usually happy to have something more exciting than off-leash pets and minor traffic violations.