I'm healthy and enjoy a good walk, but I wouldn't really want to bring luggage a mile from an airport, especially not if the weather isn't nice; it seems rare for foot traffic out of airports to be particularly easy.
I walk nearly a mile (1.2km) just to get to the nearest bus stop (that buses come to often) from my airport. I only travel with a backpack though. You're right in that they don't have sidewalks though out of the airport area.