I will mostly use them in place of my short step stool, in my studio, to get my eye up level with the view finder when taking photos with the tripod fully extended, or when I want to shoot down at a subject. At time, these seem better than a small step ladder. I never had my own studio before building one for myself last year, but I have been in and out of photography since being a year book photographer in high school, and have used the common, and usually beat up version of Apple boxes on stage and in studios before. In my junior and senior years in high school, I carried a huge and heavy old Graphlex wide format camera with the flat cartridge film cases back then for shooting sporting events. One strap around my neck for the camera, and the other (almost the same weight) for the leather case containing 12 cartridges (24 pictures). This old man could never do that now. It took too long, but thank goodness for smaller higher quality digital cameras that can put hundreds of photos on a card not much bigger than two postage stamps. After graduating high school and college, I ran a summer stock theater for one Season with 1-2 new movie or stage shows each week. I've been in and out of photography many times since then. I even owned my own commercial photo retouching business 18-22 years ago. Trust me when I say that none of the women in magazine photo ads are really as perfect as they appear. I was one of the one's who cleaned them up, removing moles, scars, sags, etc.
Apple Boxes are just a handy way to get the photographer, camera, equipment, props, or anything else at the ideal height. The 8"height size can even be used on-end for a seat for the model, or yourself. I have made quite a few boxes of this similar design over the past 5 years or so, many of them becoming tool boxes for some of my tools that had so many small accessory parts that I was afraid of loosing them unless I made a special box to keep them together in. Search my posts and you should find photos of some of these other boxes. Box jointing the corners using an Incra I-Box jig on my table saw and using a Freud SBOX8 blade set makes this part easy, and almost fool proof. Since getting them I have made a lot of boxes using box jointed corners.
Without a studio or stage environment, Apple Boxes don't lend themselves to very much use, but are very handy when working in a flat floor environment like stage or studio. A short stepladder taken on outdoor shoots is much more useful. I have an old set of nesting square boxes, open on one side, and nested in a box, that I use when placing small products at varying heights for product or small item photo shoots, and usually covered/draped with a smooth or fuzzy cloth material. These Apple Boxes tend to be a bit large for this type of work, but may get used for that as well. There is such a thing as a Half Apple Box, where the entire set is 10" X 12" with the same 8", 4", 2", and 1" height. I may make myself a set or two of them later, but I don't feel the need for them yet.
I built the studio upstairs in a spare 18' X 26' 2nd master bedroom of my home last year, but then some heart problems kept me from finishing it. Since early this year I completely re-arranged it, moving my 6 backdrop roller system and moving even my lighting equipment to the ceiling, using mostly my design of overhead support system for my lighting equipment. This removes almost all of the need for tripods and on-the-floor wiring, eliminating almost all of the tripping hazards that are usually part of a photo studio.
I'm going to try to put together a full description of all of this and post it.
Overhead supported lighting methods for large photo/video studios are very expensive and complex. My way takes a little bit more time to relocate lights, but is much cheaper to install and operate, most of it being made from readily available materials too. Today, the only things touching my floor are the camera tripod legs, the table with the Apple Boxes on it, and the bottom edge of the gray backdrop. I used 4 monolights with softboxes for the Apple Box shot, but all are supported from above. Even the electrical power to run them is on the ceiling. Radio communication between the camera and lights flashes the monolights, and a WIFI link sends the taken photos from my camera to my laptop, as they are taken and without wires. My only wish is that I had a 10' ceiling to do this under. 8' works, but 10' would be much better.