Much like Wassies sporting Doughnuts, Wassies that are observed with ice cream cones on their heads do so in order to 'save it for later'.
When a fortunate Wassie manages to get its flippers on an ice cream cone, it takes a quick lick at the ice cream only to realize that the ice cream is simultaneously delicious and too cold for the Wassie. And so the Wassie decides to put it away for later by simply sticking it onto its head.
Needless to say, the ice cream quickly melts at room temperature and the Wassie is left confused as to where its ice cream cone went, which can lead to paranoid and aggressive behavior towards other Wassies. This is normally aggravated by the fact that other Wassies are attracted to the melted ice cream and will often approach the ice cream covered Wassie to lick the flavor off it as it swings its flippers at its fellow Wassies in a fit of rage.
