Sharp-eyed readers have noticed a change in the bar codes on some coupons, and they wrote in to ask about them. Q: "I have used coupons for many years, but I notice that most coupons now have two bar ...

Sharp-eyed readers have noticed a change in the bar codes on some coupons and they wrote in to ask about them. Q: “I have used coupons for many years but I notice that most coupons now have two bar ...