I strongly disagree. Straight glue might resist pulling apart, but it has very little shear strength. This is why wood workers use different types of joints. (not the green kind) Joints, number one, increase surface area for the glue. The more glue the stronger the bond. Number two, joints create strength laterally, or increase shear strength. Some joints include, mortise and tenon, dovetail, biscuit, and dowel. There are many more but those are usually the most common. I will say that gluing and clamping pieces together that which are non structural, like OP's mentioned Apex utility box, will be just fine. I'm more talking along the lines of structural projects like aquarium stands.
If you're using a pocket jig with the correct sizing of material and length of screws it will be plenty strong for 99% of applications. If you're worried about strength, add some glue. In this case, the screws will add lateral strength to the joint and glue will make the joint even stronger.
To the OP, just please do not just put two pieces of wood together and glue it for anything structural.
I personally have the pocket jig in the first picture. I've used it to make all kinds of furniture and several aquarium stands. Heck I don't even have the locking clamp for it. I do mean to buy it eventually, probably when I build my kitchen cabinets when that time comes, but I just use a standard clamp instead and I don't have any issues. The big expensive one is more for cabinetry and furniture making, I'd highly recommend just getting the cheaper one. Oh, and using the kreg specific screws does make a big difference too. Also pay attention to hardwood vs softwood screws for your specific application.