They're talking from a North American perspective (probably). In most of Europe, there are plenty of outdoor and other free exercise opportunity. Another downside of the incorrect build environment (poor city planning) is that Americans simply don't have built-in ways to move their bodies. When I spent time in Eastern Europe, there was literally a free tennis/basketball court across the street. And a variety of other courts, including outdoor gym. And when house sitting around, there was nearly always an outdoor park with greenspace for strolling, exercise. All free.