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.
I think they’re still wrapped in foil in Australia, though I haven’t had any in a few years. I don’t think I’ve ever seen any eggs come wrapped in plastic, although the bags the foil eggs are in are plastic