OK, one more try. Do you pay fuel tax? This says you do not. As a result, other taxpayers are picking up the tab for port construction, maint., etc. Maybe you don't appreciate it but the titty is in your mouth.
"Fuel subsidies.—The federal government taxes most gasoline and diesel fuel used in the USA, the money from these taxes being earmarked for road construction and maintenance. If the government treated land-based and water-based transportation consistently, fishers would also be required to pay such taxes and the money would go toward port construction and maintenance, the Coast Guard, and other public facilities and services that fishers use. But in contrast to land-based U.S. users of gasoline and diesel fuel, commercial fishers are exempt from all federal fuel taxes, providing the fishing industry with a large subsidy. Commercial fishers are also exempt from state fuel taxes and sometimes state sales taxes on fuel."
As a side note, Oregon also waives fuel taxes for commercial fishermen.
http://www.lenfestocean.org/~/media/legacy/Lenfest/PDFs/sharp_sumaila_2009.pdf?la=en