Legs are natures' intended way to get around. I don't get why people even wonder if processed alternatives like cars or bikes might be superior to running.
Isn't that what GP is saying though? Cars and bikes are superior to running in the fact that they take you to the destination faster. But a person running everywhere will undoubtedly have better development of their leg muscles than a person driving around (assuming no other physical activity). So, at least in the context of leg muscle development, running is superior to cars and bikes.