I don't think it's trolling, it's just having a lighthearted moment in an unexpected situation. You can't blame individuals for doing what they're supposed to do, i.e. replying to emails; at that point it's the moderators' jobs to kill mailing permissions or something.

>the unprofessional and juvenile mindset, taking pleasure in annoying everyone else, is enraging all by itself even if no practical harm was done.

Working at your company sounds hellish.