I think walking VS driving is also about convenience.

In the example we're replying to, the shared suburban street has a marked median (implying medium traffic), minimal shoulder, and no sidewalk. While the houses and foliage are very nice, it feels a little unsafe to walk on. Presumably the train station has nice parking, so driving is quick and easy to do. Choosing to walk in this case is more for leisure or for exercise.

In the city though, driving is a whole other thing. Storing a car and finding parking just to go 1 mile is a huge pain: it's much simpler just to walk it. Walking in this case may be for leisure and exercise, but it's also for convenience.