Many petshops locally here sell dried pellet forms of iguana food, which I find seriously misleading as a diet. Many other processed foods, marketable and convenient foods instill the need to not research propor diets, etc, etc.
Much like you see with the dog and cat foods and products, they are there to provide a service to those that like to spend money and feel like they are helping while adding convenience for the purchaser. Same thing with substrates, 'play toys' and husbandry 'gizmos' that fulfill the market with uneeded impulse items. Just a way to make a quick buck for the manufacturers. Not really proper, but heck, we as people like to spend money on 'neat' products over what is correct and otherwise 'boring.'
All in all, it is just silly, pointless, and in my opinion harmful to the overall hobby. Those that indulge in these products are usually those less informed, and therefore are only purchasing due to the convenience and lack of understanding herps as a whole. Plus, it helps shops with their need to pay for all the overhead by selling big priced, low quality products.