I suppose it's not surprising as they are tough little flowers for all their seeming delicacy. They just keep flowering through snow, ice or gales as a symbol of hope over adversity.
According to legend, snowdrops became the symbol of hope when Adam and Eve were expelled from the Garden of Eden. When Eve was about to give up hope that the cold winters would never end, an angel appeared. She transformed some of the snowflakes into snowdrop flowers, proving that the winters do eventually give way to the spring.