Who introduced gift coupons to promote sales?

The first Gift COUPONS.

The first Gift COUPONS were introduced by Benjamin Talbert Babbit of New York in 1865 in order to discourage purchasers of his soap from the idea that they were paying for the wrapper. Each wrapper was over printed with the word “coupon” and 10 coupons entitled the customer to a ‘Beautiful lithograph picture’. Other gifts were added as the idea grew in popularity.