they have their place
as i see it there are three things that rfid could give you in the distribution business.
1. a longer serial number than a traditional barcode, so that each item can be uniquely numbered rather than just batch/type numbers. (think ean numbers on products, it tells you the product type, but theyre all the same one)
this can be addressed just by using more dense barcodes, like any number of the 2d barcodes that exist and are seeing increasing use by postal couriers.
2. storing data with the product itself. well the storage involved is pretty limited, typically a few kilobits of data. you could just keep slapping on extra barcode labels at each stage ;)
3. reading the data from a (short) distance and many at once. Now this you cant do with barcodes, and is a massive boon to the likes of airports. it could massively cut the time it takes to locate that one passengers bags from an entire aircraft full. especially when traditionally they had to not only physically see each bag, but locate its tag and orient it in order to read the name. medium range rfid tags could allow the elimination of entire packing crates full in seconds.
the other field where rfid is obviously a boon, is the places where smartcards were previously useful but not always practical, in say transport charging systems, door access systems etc. where the continual make/break of physical contacts leads to errors and damage.