QR Codes do work rather well actually in different contexts, they are very robust. Upside down, from across the room, weird lighting... Also, in the Chinese con

QR Codes do work rather well actually in different contexts, they are very robust. Upside down, from across the room, weird lighting... Also, in the Chinese context, everybody knows what to do with it and what to expect to happen if they scan it. The farmer coming into the city on a trike selling fruit even accepts payment by QR code :)