I find this all a bit strange to be honest. What does ringing up the receptionist prove to anyone? Joy won't take any calls herself, so probably won't give a shit about people ringing. And saying it takes up their line; most large companies have more than one line to ring, so unless it is a coordinated event with multiple people ringing for hours at a time it won't disrupt their business. All it does is piss off the receptionist, and have zero effect on the people that should be feeling the bile. I won't take part in such behaviour, not because the people involved don't deserve it (although that is questionable), but because it is absolutely pointless and will achieve nothing. If you disagree, name one CEO or owner who has fallen on their sword because of a few prank calls.
Note: when I say it is questionable, I mean it from a moral standpoint; I'm not a fan of hating people.