The city deactivated most of the pedestrian buttons long ago with the emergence of computer-controlled traffic signals, even as an unwitting public continued to push on, according to city Department of Transportation officials. More than 2,500 of the 3,250 walk buttons that still exist function essentially as mechanical placebos, city figures show. Any benefit from them is only imagined.
Here at MIT there are definitely some "Close Door" elevator buttons like those described above — I’ve always assumed that they were part of some Course 9 experiment to measure the mood/stress levels at MIT.
Followup: Monday’s NYTimes editorial — Press Here to Control the Universe