I have been using coupons at Costco since they started sending them. The first couple of times I used them I dutifully cut them out like I do at our other grocery store. Each time I tried to hand them over the cashiers waived me off; they didn't need the coupons and would either punch in some unknown code or scan the coupon booklet (bar code near my address). The coupons would then be deducted for all the items I purchased. Great, I thought. Modern technology at work. I continued to use coupons and after the second or third time stopped... read full review »