When talking about stick fighting, especially here in America, I personally believe that the Shillelagh needs it's place at the table. The Shillelagh was originally a weapon used by the Irish after English law made it illegal for Irish Catholics to own and carry blades. The Irish naturally brought it with them to America. When in the 1800's the major East coast cities needed full time police to keep the peace, they turned to the Irish gangs and stick fighters. The original Irish police officers had two sticks they used, a day stick and a larger night stick.
The Shillelagh is a very quick, effective style of stick fighting, as evidenced by those early police men. Not to mention most people think it is a walking stick, so you can carry it everywhere. Not to mention, it's fun. At least to us crazy Irish boys.