Walking/Biking also allows me to instantly change my plans, even more so than driving does (try turning around instantly in a car). What do you mean "low large countries work"? The absolute size of a country is irrelevant (what New Yorker cares what malls there are in Kentucky?), what matters is population/service density. The US has a 50% larger population density than Sweden, so it should be able to support at least as dense cities and services. The difference not economic or technical, but cultural.