Our local paper has a story that the Sunset Park Ferry that leaves from the 59th street terminal is in danger of being discontinued due to low ridership. Do people in Sunset Park actually know that it's there? I happen not to work in Manhattan so I have never had occasion to use it. However, I would be willing to bet that if you ask most residents of Sunset Park about the ferry most would tell you they didn't know it existed.
Oh, occasionally it makes the local paper The Sunset News our local free publication that prints 30,000 copies. But probably maybe 10% get read. The paper is also not widely distributed outside of a small stretch of 5th avenue from the 39th street to roughly 60ths street.
In any case, the ferry would probably get more ridership if people actually knew it was there and if they also knew that there is plenty of parking on the pier where you can leave your car for the duration of your work day. As it is, if the Ferry wants more riders they should make sure that more people know about it and that is a matter of marketing.