I've been working "Stand-by" and "on-call" shifts since i was 17, and been working nightshifts every other 2 weeks for the last 12 years, and i can tell you, you never get used to it.
one day i'll have a daytime only job...but for now working nights earns me enough money to provide for my family, without my wife having to work.
So she is around to beat , uhm, raise the kids 24/7 and i can tell you, they need that.
And if this picture were taken in the middle of the night, i might not be having such a big smile, though...