Byron,
I am 61 and have walked Chambers Bay a few times and will do so again this week. Also, the people at Chambers Bay tout the course as a "walking only course" so I think they would be shocked to read your comment. There are a few uphill walks like #4, #7, #8 and #12 but they are not bad.
Also, someone mentioned PGA West which, in my opinion, is easily walkable.
I have played Tobiano, written up here a few months ago, in a cart. With the constant up and down of the gullies or ravines, it is in my opinion, unwalkable. From the pics I have seen of Cape Kidnappers, it seems to be more like Kidnappers than any other course I have noticed and the similarity I am referring to is the gullies and ravines, not the rest of the architecture. It was very interesting to see what Tom mentioned, ie the bridges. I think Tobiano could use some bridges to make it walkable and that would definitely change my opinion of the course.
Otherwise, in the northwest, Furry Creek (Sean Leary's favourite), Chateau Whistler (RTJII) and a few of the courses in the Rockies are definitely unwalkable.