I'm just wondering if (some) cameras have an option to retain the top image without it being erasable. Then you can take a picture of a card with your address on it for the convenience of someone who might find it. My gps has a power-up screen with my name/address on it for just that reason.
Like Bobntg said, old news in Quebec, where they are horizontal as well as shape-specific. But they like to do things differently in Quebec, and it likely generates more revenue from visitors who are confused by the lights.