All persons shipping from, into, within or through this State may designate the route or routes by which such goods shall be shipped, subject to such reasonable exceptions and regulations as the Public Service Commission shall from time to time prescribe, and it shall be unlawful for any person other than the holder of the bill of lading to vary such route so designated or to ship such goods by any other route or to receive such goods if so diverted, unless the route so designated shall be interrupted or be incapable of being used at the time by strike or casualty preventing the running of trains thereon.
S.C. Code § 58-17-2740