Nothing contained in this chapter shall be construed as permitting a common carrier by water to discriminate between competing shippers similarly placed in time and circumstances, either
(a)
with respect to their right to demand and receive bills of lading subject to the provisions of this chapter; or
(b)
when issuing such bills of lading, either in the surrender of any of the carrier’s rights and immunities or in the increase of any of the carrier’s responsibilities and liabilities pursuant to section
1305 of this Appendix; or
(c)
in any other way prohibited by the Shipping Act, 1916, as amended [46 App. U.S.C. 801 et seq.].