While barcodes need to be manually scanned, RFID simply broadcasts its presence and data to electronic readers. Vint Cerf. … one of the inventors of the internet … now employed by Google… told Click: “What everybody worries about is that these identifiers will be used not to keep track of the object, but of the person associated with the object and then there’s a Big Brother scenario that everybody worries about. … Metro sees RFID working for it by having food traceable back to the farm, queues cut to nothing, and shelves that shout when they are empty.
… The fear is that what we buy will be forever linked to us. In the nightmare scenario, an innocently discarded soft drink can could end up in what later becomes a crime scene. RFID could open a whole new field of forensics where the tag on the can removes any reasonable doubt.” – BBC