NeoMedia has patents that cover this technology:

Patent #6,651,053 — Interactive system for investigating products on a network

An interactive search system for use with a global computer network, e.g., the Internet, using a search identifying barcode to rapidly and effectively obtain a supply of related information for presentation to a user. A computer, either landline based or mobile, may be used to input a UPC code, taken from a package or advertisement or prestored in the computer, to an implementing server on the network. The server contains a database of product and manufacturer identifying UPC codes and uses the input UPC code and the database to identify the manufacturer and is programmed to then perform a search of the network to locate sites relating to or operated by the manufacturer. Also, the server may search the network on a product basis to locate other sites containing the UPC under search. Using “parsing” technology, the server “pulls out” the product description, transmits it to and places it in a random access memory (RAM) or storage of the computer, and proceeds to perform further searching relying on the product description to uncover relevant information. Accordingly, using a single input, a collection of product-related and manufacturer information is quickly assembled in the computer available for a user’s consideration all at once at any time.

I do like geo-based games though. I played a few even without AR technology. (Perplexcity event in london was particularly fun).
I can certainly see a *lot* of those games springing up in citys once gps becomes standard in phones.

Oh, also, BreadCrumbz link seems broken :-/