49 U.S. Code § 13713. Food and grocery transportation
(a) Certain Compensation Prohibited.—
Notwithstanding any other provision of law, it shall not be unlawful for a seller of food and grocery products using a uniform zone delivered pricing system to compensate a customer who picks up purchased food and grocery products at the shipping point of the seller if such compensation is available to all customers of the seller on a nondiscriminatory basis and does not exceed the actual cost to the seller of delivery to such customer.
(b) Sense of Congress.—
It is the sense of the Congress that any savings accruing to a customer by reason of compensation permitted by subsection (a) of this section should be passed on to the ultimate consumer.