I am in the right seat at a regional. The only individual I have ever witnessed engaging in such shenanigans was the guy occupying the left seat at said regional. I refuse to participate in anything on guard unless necessary for an emergency or by ATC request.

I can relay to you one story from GA flying on the matter: Flying up the coast at low altitude I picked up a weak ELT signal and reported it to ATC. ATC calls up a couple of airliners in the area and asks if they hear anything "negative". I lost it... but got it again, it was still there behind the squelch. I turned around and went back, it got stronger, and kept after ATC about it since no one else could receive it. It turns out it was the weak 121.5 signal emitted by an EPIRB. A fishing boat had sunk. I read the next day, a couple were rescued, one not so lucky.

If that's not a sufficient reason to cut it out on guard (both the immature stuff, and the 'guard nazi' behavior the Lego movie was satirizing), I don't know what is.