My understanding is that broadcastify is civilians with scanners who stream the output. In other words, if the police systems are scannable (i.e., not spread spectrum or encrypted), they can’t stop it.
There have been occasions where Broadcastify was requested to shut down a feed (The Dorner incident was one), and they’ve complied, but usually there’s no request. The feed’s actually about two minutes behind the actual radio traffic, most departments don’t put private info on the air, and to the extent that it keeps the lookey-loos at home, it’s sometimes helpful.