I don't think it was staged, but I do reckon that they 'staked out' a likely spot (possibly having seen others fall there) until they got good footage. Footwear wasn't necessarily his problem, lots of runners have good ridged soles with good grip. He was just walking too fast for the conditions. His other problem was that he had one hand carrying the bag, which meant it wasn't available to give support or break his fall. It could have been quite serious if he had smacked his head on the wall or the ground.
I fell in Dublin city centre yesterday, despite walking quite carefully. It was treacherous around Trinity and Pearse St. As usual in our car centric society, pedestrians are an afterthought, and gritting of pavements was forgotten about for the first week.