Some say that physicists do not argue politically:
"A vehicle's fuel consumption is the direct result of its total resistance to motion. This includes overcoming inertia (Newton's Law), drive friction, road type, rolling resistance, and air resistance." Resistance and more resistance. We ourselves sometimes experience resistance to motion, so we want to simplify things. Checking tire pressure, for example. How movement-intensive can a tire pressure check at a gas station be after the valve cap has rolled under the car, the washroom door is locked, and we don't necessarily want to get behind the wheel with our soot-smeared hands? With TireMoni, checking tire pressure is much easier, with less stop-and-go.
"During stop-and-go city traffic, it is estimated that overcoming inertia is responsible for approximately 35% of the vehicle's drag. Driveline friction is approximately 45%; air resistance is approximately 5%; and rolling resistance is approximately 15%. Overcoming inertia no longer plays a major role at constant speed on the highway. For these conditions, it is estimated that driveline frictional resistance is approximately 15%, air resistance approximately 60%, and rolling resistance approximately 25%." Quotes from: http://www.tirerack.com
Rolling resistance can be easily improved: Retrofit TireMoni.