I have a specific example. Outside Gate 4 of the main Warner Bros Studio lot in Burbank, CA, at the intersection of Olive Avenue and Hollywood Way, the southwest corner. The button to cross Olive and head north on Hollywood Way (the one I would press to get to Taco Bell) was vestigial for years. During the day at least, the traffic light cycle would automatically trigger the pedestrian WALK signal some three or four seconds before the north-south traffic lights would go green, which was highly unusual but necessary so pedestrians could start crossing before all the right-turn maniacs on southbound Hollywood Way could dive through the intersection on their way over the hill.
Anyway, sometime in the last year or so, that button became functional. Surprised the hell out of me. Delayed my Taco Bell fix for an entire traffic cycle.