I fly my seaplanes (and float planes)off of snow but only when the snow is new , packed ,or has not iced over. When it gets very hard and or ice covered the seaplanes (and float planes)stay home and the ski planes come out. The hard/icy snow is rough on the hull and rudder.
All of my seaplanes (and floats for that matter) are glassed on the bottoms and slightly up the sides before paint or covering is applied.