Surely this can’t be a realistic depiction of a wasteland when you still have huge boxes of Swiss chocolate just lying around:
It’s a bit sad that someone must have already eaten all the chocolate out of this particular one, since all it contained was chocolate-unrelated medical items. But perhaps the previous owner simply finished off the chocolate and thought it would be a good idea to store first aid kits in the box instead of throwing it away. Resourceful, and in line with the whole post-apocalyptic theme.