I had to wait today whilst the till operator wasted MY time wrongly entering a 4 number code, which she was told twice by a colleague and still got wrong, to void an item. That's my time not hers being wasted - she'd still be there, getting paid whatever she was doing. Ok so there's nothing that can be done about THAT - but what about these people in queues who react with shock when asked for payment and ONLY THEN look in their purses/wallets/pockets for money (or worse, credit cards) or who pack their shopping THEN pay afterwards - hang on, there's a queue here!