The McDonald's is in the International satelite terminal. For the crew to be travelling onto another domestic destination from this photo, I remember you get the train to the other terminal and have to pass customs. The domestic terminal does not have much there let alone a McDonalds. Therefore they must have been travelling onto another country when the photo was taken?
I suggest they could have either stopped in Malaysia before this photo (eg, Kuching, Sabah, etc) then traveled back to KL and transit off to another country, or they are in transit from another country onto another country not stopping in Malaysia.
Brunei could be a possibility?