I love QR codes and used to put up QR code stickers around town. I hate them for menus though. I sometimes like to go on walks without my phone and stop in somewhere for a meal. Or my phone is dead. Or I just want to have a meal with someone without any phones distracting us. The only implementation I've seen of this that I thought was neat was at a restaurant where it opened up to a website where I could place the order and pay on my phone.