Central air systems that were retrofitted often use downspouts to route the freon pipes from the compressor to the cooler units inside the house, usually in the attic. They may pass low voltage control wiring that way too. I doubt that the code would permit power cables, though. Downspouts look prettier than exposed pipes, and offers some physical protection to those pipes as well.
As for the second picture, I think that there is a common mis preception amoung the public that materials listed for use in house wiring would also more than qualify for use for making extension cord sets. As if the requirements for anything that plugs into a wall socket are less stringent than for wiring installed inside the walls of a house.
As Joe T. points out in that picture of him holding a homemade extension cord at a hotel conference, that's not true. A metal box intended for house wiring isn't designed to be tossed about like an extension cord is likely to see. The knockouts getting dented in, for example. Also the constant flex the cord applies to the clamps on the box will make them loose. This doesn't happen inside walls with house wiring. The requirements are different, not less stringent.