Similar to Jim's post above, I've found cameras to be great when a piece of kit is located in such a position that it's impossible to maneuver your body to be able to see the back/front/side, and it's more hassle than it's worth to remove or disassemble the kit. In that situation, it's often a great benefit to be able to stick your hand in an appropriate position and get a quick photo that tells you what you need to know.