No vessel employed in and licensed for the coasting trade shall be obliged to receive a pilot or be subjected to the payment of pilotage in case of refusal to receive such pilot, except ships or vessels bound to the states, territories or possessions of the United States on the Pacific Ocean, but a coastwide vessel voluntarily taking a pilot shall pay the pilot a fee which is no more than the fee for pilotage as prescribed in the case of a vessel bound to or from a foreign port.