Each bar is wrapped in cellophane, which are then wrapped in the normal outer packaging. To make the 4 pack, they simply took 2x two packs and put them on a cardboard tray,and then wrapped those.
I don’t think I’ve ever gone through so much unwrapping for candy.
Come to think of it, nowadays you can still buy certain things in bulk, but a packaged option exists too. You could carefully choose and weigh the individual potatoes you like, or you could just pick up a bag that was prepared earlier in some potato factory. The same things applies to many fruits and vegetables too.