Unfortunately Diddley Dee, if ATC don't become the "guard police" who else will?
I'm fed up with hearing the constant calls on 121.5. If it is a mistaken call to the handling agents, then so be it. We've all stuffed up R/T calls at some point, but as has been mentioned before, the "guard police" can make it worse. Shut up and let the person learn from their mistake rather than compunding the issue.
Just have a bit of discipline and keep your mike shut unless you need to make a call.