I am a 999 op, and to be honest I agree with you. However, some of the management would not be inclined to agree with us.
It takes a lot for somebody's phone to even be disconnected, I am talking those putting in serious calls saying that somebody is in a burning building, as an example, and even then all it will be is a disconnection. I have never experienced a prosecution.
To be fair, MOST calls that are hoax we root out fairly quickly and no resources are sent, and a lot of them provide us with amusement.
It is a rare situation where resources are kept away from real incidents because of a hoax, and doesn't happen anywhere near as much as these stories would have you believe. We know when we are dealing with time wasters 95% of the time. It is purely a deterrent.