They only go naked because they are attention wh*res, who know that their nudity will shock and offend a considerable segment of society (those of faith and those with different morals). They rub their nudity in the face of this segment as a direct insult (no different than shouting the "N" word in a black church). They know that they can not win their argument intelligently, so they result to cheap pallor tricks and insults.
It is has quite some time since anything in public in the US has been argued intelligently. It is all about being media whores.