Sounds like a coupon nazi, but hey at least she didn't say anything else after u gave her an attitude. Typically, I use a percent off and rewards yet they still give me a hard time. Never tried combining percent off with $ off $ or doing 2 transactions with the same cashier. I don't want to see how rude they can get as if they are already rude when customers use coupons. Our cashiers said Staples rewards are coupons so using it alone is like already a coupon so why stack another coupon. Ironically, when they advertise to get me to buy the item they say "hey buy this item and u will get back rewards which u can use it like cash at Staples."
After you receive the rewards they will claim the rewards as coupons. Ha!