The real point is that a mile walk, for people without mobility issues, takes about 21 minutes. You don't need to prove your awesome commitment to walking by walking 16 miles. That's recreational walking and/or exercise, not "getting around" walking. You don't convince people that modest distances can easily be a part of normal daily life by setting out on a 5-6 hour walk. Of course plenty of people don't live within a mileish from good transportation that takes them where they need to go, but for those who do, the "last mile" really isn't a big deal.