Nobody in Mcmurdo is out of place. It attracts people from all walks of life and all ages. Plenty go for the experience, but be forewarned that you are being hired to work and that will be expected of you. Most work six days a week 10 hours a day including an hour for lunch.
It doesn’t sound like there is much time left over for fun, but there is. You work in the same place you live so the minute you are off work you get to do your own things. In the summer it’s especially nice because the 24 hour daylight means you have hours of available time before going to bed.
Explore the base, Climb Ob hill, walk to hut point.
Climb castle rock. Walk to Scott base (or take the shuttle)
Ski out to the airfields. etc etc etc.
Work hard, play hard.