Even that I'd call somewhat petty, but it is more defensible if it's insulting to you when you hear toilet noises from your phone, and you are totally in your right to tell it straight to the person who is calling you, that it's hard to hear him behind all farts and flushes. That's ok. People here seem to be complaining that somebody else is talking to somebody else on a phone while being in the public (office) toilet. I mean, I kinda understand if it distracts them from their business due to some psychological difficulties they may have, but that's the public toilet design fault when you cannot feel isolated enough, not the guy's talking.