These post are designed for soldering wires to them and were pretty common. Heating the post up will not cause it to fall off because it is peened, riveted, or swaged, so it is firmly fixed on the circuit board. After being swaged to the board with the solder pad underneath which makes a good mechanical connection, the swaged head of the post is soldered to the pad to insure a good electrical connection as well.
As the video shows, the wire you want to connect is bent around the top or the bottom turret and is soldered in place. Here is a cross section of the way the posts are fixed to the circuit board.
Oh, and some of the hollow posts were used to insert a component lead up through the hollow post and the short end of the lead was bent over to hold it in place while it was being soldered. The photo I just took shows one of these from the backside of the board. The lead that goes into the hole in the metal post is the connection as there is no pad or run on this board.