Diversity in Airports

Airports have a great diversity of people, and not just because there are people from all over the world.

Some people stand in place on an elevator while others run up the stairs to pass them.  Some sit asleep in their gate for hours while others rush past them, hoping to catch their flight before it leaves.  There are people grudgingly working in McDonald's, while someone eating a hamburger is on an important business phone call.  Some people in Hawaiian T-shirts arrive home from their vacation while others in camouflage return home from the war.

This is the part where I would explain what it means, but this time I don't really know.