R.I. Gen. Laws § 11-19-11
No person or corporation shall, either directly or indirectly, give, sell, or distribute any stamp, trading-stamp, cash discount stamp, amusement stamp, check, coupon, or other similar device with the promise, expressed or implied, as an inducement to the purchase of some article of goods, wares, or merchandise, that the holder of the stamp, trading-stamp, cash discount stamp, amusement stamp, check, coupon, or other similar device is to receive in return, on presentation, some gift, prize, or gratuity, the nature and value of which are unknown to the purchase of the goods, wares, or merchandise at the time of their purchase, the promise to be fulfilled only upon the presentation of the stamp, trading-stamp, cash discount stamp, amusement stamp, check, coupon, or other similar device, together with the number of like stamps, trading-stamps, cash discount stamps, amusement stamps, checks, coupons, or other similar devices, as the issuer or redeemer may elect shall be redeemed at any one time.
R.I. Gen. Laws § 11-19-11