Selling Coupons May Not be Illegal, but using sold coupons is

According to the Federal Trade Commission: "There’s only one legitimate way to use a coupon: Cut it out of the newspaper or other source and use it toward the purchase of the designated product. A coupon is meant to be used only by the consumer who buys the product for which the coupon is printed. Selling or transferring coupons to a third party violates most manufacturers’ coupon redemption policies—and usually voids the coupon." http://www.ftc.gov/bcp/edu/pubs/consumer/invest/inv06.shtm