I was told that shipping gondolas full of snow south was a common practice at Watertown, NY, the “snowiest” point on the NYC. The story I heard was that the yardmaster would start hoarding gondolas every year around Halloween for “prospective loading” … even though there were no customers in or near Watertown who shipped in gondolas. I think he even favored gons belonging to southern railroads as being more suitable for that “prospective loading”.
As they were filled with snow, they would be released as excess and routed back to their owners in the south. I often wondered what their people thought when they received these gondolas with a foot of water sloshing around in them. [}:)]