I'd be able to kinda understand if the MC tried to sell simple film cameras or polaroids, so he could keep materials to make photos monopolized, and so that there wouldn't be any need for the use of electricity, because there is no generation in that world, but this is just utter bullshit (all the digital cameras and, quite possibly, the presented polaroid are just gonna turn into bricks after their batteries run out of energy (+ just how the hell could he print those photos right there at the store? Did he already bring there a generator, voltage stabilizer, PC and printer?)).