New York camping over the memorial day weekend

I am surprised that Liberty Harbor has sites for Memorial Day weekend but perhaps it is because most want to get away from the City that weekend than come to it. I have looked for the last month for Memorial Day vacancies in PA,CT, and Mass and everyone is booked. Most just laugh when you call and say that they booked for this year last Memorial Day. Upstate NY - most probably the same thing. You may find a cancellation but expect to pay a lot more for sites on Holiday weekends.