Your neighbor's child is selling discount books to raise money for a school organization. You are happy to help and buy one of these books because of the value and the amount of money you can save using the discount coupons. You take your car to Larry's Quick Lube for an oil change and present a valid coupon from the discount book. Larry refuses to honor the coupon. Do you have grounds to require Larry's compliance with the discount? If so, under what doctrine of law? Discuss.