Pretty much the entire ocean transportation industry, with the exception of container shipping, works this way. Prices are largely based on predictions of market conditions in your load port at the time of loading, and the the same wherever you’re sending the cargo.

If you’re trying to load cargo in an area with an undersupply of vessels, you’ll pay a lot for the opportunity. If you’re sending a ship to an area with an oversupply of vessels, you pay more for that because the company renting it to you doesn’t have good confidence in its ability to get a contract once your cargo is offloaded.