Swipe your Idea

I seem to spend a considerable amount of my life at Tesco's. I even have my own Clubcard. However I do not have one of the ones which you can attach to your keys and so add it to your keyring collection. This got me thinking. Why don't all stores who have their own store card, have it in a convenient keyring form, or even better they could incorporate it into a fashionable bracelet, which means customers could simply swipe their hand when they are purchasing an item.