> > Everyone I know checks their receipts.  Even if most don't now, 
> > they're going to start when they repeatedly get home with items in 
> > their cart that were added by pranksters and hear horror stories of 
> > all the items people paid for because the scanner read a stray tag.
> >
> > Also, you can wait in line behind me and people like me a 
> few minutes each 
> > while we check the receipt :).   Then you lose the speed 
> >
> >   
> I wouldn't say that exactly, with an RFID system all 
> checkouts would be 'open' so unless it was the night before 
> christmas there generally wont be a line at a checkout. The 
> RFID tags can be placed inside the packaging in many cases by 
> the manufacturer, preventing casual theft. 
> How does an RFID system handle things like buying things in 
> variable quantities, grapes/nuts/coffee etc...


Same way as it's done now. 

Not selling it is the easiest way out, followed by pre-packaging.  You won't
be able to buy a single carrot, you get to pick from 3 or 4 bag sizes.

It can be handled the same as meat/cheese etc, where it is weighed, wrapped
and has a custom label applied.  If you look, you'll see the bar code will
start with '22', and you'll find the weight (sometimes price) of the item
somewhere in the rest of the number.

For RFID, this means you need to be able to provide programmable (one time)
ones in the form of a label.  Price (of the labels) is the holdup here.

Another option is to have split checkouts, RFID & non-RFID.  You take the
fruit & veg out of the cart, they get priced (by a human), push the cart
thru the scanner to handle any RFID stuff, toss the rest in and head for the
car park.

More likely is to have the cart weighed & priced.  If there's a mismatch
(caused by fruit) you go to a normal checkout, and handle the non-RFID (as
well as errors) there.

Tony

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