Like pillow talk, except you are NOT getting laid, no matter what. It's an intimate conversation between a cashier and the customer, restricted to regularly returning customers. Cashiers do not make commision, there is no reason to snow-job a customer into spending more money. Less than 25% of customer/cashier interactions will contain cashier talk.
Cashier: Hi Tom, how's the wife and kids? Littly Suzy still down with the flu?