a local running club used to have a message board back in the early internet days, and it too allowed anonymous posting. people got their feelings hurt, and complained and complained, finally they required everyone to use their name.
when it was anonymous people would people would point out when a race was short, had poor traffic control, or started very very late, did not have water.. they would call stuff out that was bad. this helped inform the running community what races to avoid, etc..
once everyone's name was out there the board turned to garbage because nobody would be honest. it just became a big rah rah "you ran so great! blah blah blah"