It was a nice balance. However, there were more significant differences than just activity level. The original person, the one I brought up, ate like most people who go to McDonald's do. Big Mac, fries, Coke, all the fat, greasy, sugary, nasty stuff. The second person chose the more healthy (less unhealthy?) options that people give lip service but I have yet to have witnessed anyone actually order at a fast food place.
Both are extreme cases and not ones that the average person is likely to actually come close to. However, the first does offer a glimpse into the health risks of an unhealthy diet, just as the second offers a glimpse into how important factors other than diet are. Both hopefully things that all of us here already realize.
Of course, if all Americans would just take a little personal responsibility for themselves and care about their health, neither of these "studies" would have even been done because the topic would not be an issue. Too bad people would rather blame someone else for their problems rather than take responsibility for their own actions.