FQ,
You need to remember that these workers are also on the rig all the time. When they get done with their 12 hours on, there is limited activity. There are some creature comforts, but these guys aren't out "bar hopping" all evening. They are in a fairly well controlled environment, and they are there to work, eat and sleep. Also, for those that make the cut, they are used to the riggers of 12 on, 12 off for three weeks.