This doesn't seem to be true. This site [1] lists many agencies (based in the US, UK and other countries) that will sell you a passenger ticket for a cargo ship

This doesn't seem to be true. This site [1] lists many agencies (based in the US, UK and other countries) that will sell you a passenger ticket for a cargo ship. Availability is probably limited though, as each ship can only take a few passangers: "Cargo ships can carry a maximum of 12 passengers although most vessels only have accommodation for 4 to 6 passengers" [2]. [1]: http://flightlesstravel.com/plan/cargo-ships/ http://flightlesstravel.com/plan/cargo-ships/ [2]: http://www.cargoshipvoyages.com/WhatToExpect/ http://www.cargoshipvoyages.com/WhatToExpect/