Their uses are endless. Like I said that is my mountain bike kit so the main reason I there is if I'm in the backcountry and break a frame. I could splint the frame and use zipties to hold it together. In town, the zipties could be used for fixing a broken rack, replacing hardware that might fail or fall off, allow me to zip tie a pannier to a rack if I needed to, attach a light after crashing a breaking the mount (I've really done this one), etc.

All of that stuff has been used, and useful, at least once to get my bacon home. I'm amazed that you keyed in on the zipties and not the 16p nail.