Why scan a UPC code when you can just take a picture of the cover of a book and have the product found just as fast
Surely the error rate of that compared to bar codes is much higher. For common products Im sure it works just as well but bar code scanning doesn't degrade for edge cases in the same way.
You should try it. It is remarkably great, and while I can't speak to error rates I believe that it is on par or better than a good camera-based scanner. Also: using SnapTell with my decades-old textbooks in Greek religion confirms it's not just for "common" products.
(Disclosure: I have nothing whatsoever to do with SnapTell, but I have been consistently impressed with the technology.)
Surely the error rate of that compared to bar codes is much higher. For common products Im sure it works just as well but bar code scanning doesn't degrade for edge cases in the same way.