For a mall or main street studio that specializes in portraits, it makes some sense to hire someone who can get the subject to deliver a nice smile and pleasing pose, even if they know almost nothing about photography. Set the camera to the shutter speed just below sync ( this works best for my studio strobes), aperture to f/8, and ISO to 100. Then place the lamps to deliver the lighting ratio and power for the camera settings. Now you just have to worry about focus and a smile. At f/8, you probably have enough DOF to permit focus to be slightly off without major penalty.
You see exactly the same thing every year when the studios set up for Meet & Greet Santa. The camera is locked down on a tripod of some sort, lighting is fixed, probably even focus is fixed. Just have the child sit on Santa’s lap and press the button. The camera is tethered to a computer and in a moment or two a print comes off the printer. Very little expertise is required since someone else has worked out the details, and all the photos look the same.