http://www.blufftontoday.com/savvy-shopper/2015-06-28/cataldo-dont-ask-cashiers-break-coupon-policy-period#.VbY_lc7htUQ

Many customers often try to get their cashiers to use expired coupons, leaving the cashier in an awkward position. Most store policies will not allow this, but customers often get angry! Have you ever had customers try to make you accept an expired coupon?