So while you're attempting to accomplish 'being chatty' you also have to make sure you ask the customer 100 questions. You feel like a detective when people are simply trying to buy some bread and milk. How are you? Would you like a bag? Do you have a store card? Do you want the receipt? Why can't we just assume everyone's fine, they all need bags, they'll scan their own store cards and they all want the receipt - sorted.