Not being on duty is like letting kids be in your room when you are not there. It's like holding your credential over a flame.
If I win the lottery I am going to hire someone to cover my morning duty. If it is crosswalk duty I will pay double.
After school duty is kind of nice. It's an escape from a day in the classroom. Break duty is not a major pain.
At my school morning duty is 25 minutes of thinking about all the stuff I should be doing to prepare foe class. It's amazing how 25 minutes of duty feels like a slow grinding hour, but the same time on a non-duty day seems to flash buy.
Sometimes, on non-duty days that I am totally prepared, I'll go relieve a colleague of their duty (unless it's crosswalk duty). I do it in the spirit of helping a colleague and hopefully they will cover for me sometime when I need it.