I personally would not walk to the airport from there, especially with any amount of carry on luggage. You have to walk across the section of the road under where the planes come in, and there is no sidewalk and nowhere to walk other than on the concrete divider or in the road. But there are lots of taxis that hang out there at Sunset. There is now parking for around 6 to 8 taxis inside the parking lot at Alegria, as well as seating for them to wait there in case there isn't a taxi right there. Shouldn't be any problem to catch a cab from there to the airport and it should be just a few bucks. If they are determined that they want to walk to the airport from there, leave them at Gus' Boat Bar instead. It's a shorter, much less dangerous walk, view is the same, and the drinks are cheaper! As of May 2016, mixed drinks at Sunset are $8, beers $4. Sunset has a lot more choices of food however, if they want something to eat.