Different strokes for different folks, but if thats true (and knowing its The NY Times it may very well not be true) then that is a very interesting situation. I am considered generous by most people around me, but I doubt my wife and I would be so helpful to a veritable stranger. But different strokes for different folks.
Appalachian Trail hikes?
Oh, I'm sure his wife was ...very generous.
Sounds a bit like they are swingers.