Think of the "Smokey" as a drill hat. Thats why drill instructors wear them, because they "drill" recruits. Then you have Sgt. instructors at OCS, they are there to eval and screen future Marine Officers, not drill them. Thats why they don't curse as much or (at least thats what they tell you) have a pit because they are not there to make you a good follower but a "Leader of MARINES" Thats what I've been told.