Imagination. moe's got it. If as Brin suggests, Glass is available next year then scanning QR codes is one of the brain dead obvious launch apps for it. QR codes will be less variable and more reliable (under arbitrary conditions) than OCR at that point as well as being able to hold more information per square inch. They will be quickly translatable and displayed as human readable information floating in front of your face - with little to no effort required on your part.
The information density of QR codes is much higher.
In a few years many people will also be walking around with AR-glasses (e.g. google glasses) which may very well scan the codes automatically and overlay them in the viewport with whatever they want to represent.
Doesn't it seem idiotic to duplicate what we already have? (English characters) in some arcane non human readable, punch-card-esque idiocy?
In a few years, all cellphones will be able to read english characters and words. There will be no need for QR punch-cards.