I wonder if it is to do with fraud prevention and tracking? No opportunity to add a zero and I assume, once the barcode on the bag is scanned, it is 'on the system' and someone is able to balance the number of cheques received and processed with at the central clearing facility?Does anyone actually know what the purpose of the magic plastic bag/wallet is supposed to be, other than to add to the unnecessary plastic waste that we, as a species, insist on producing?