As bending in rubber on both sides of contact patch is where the energy is lost , then as Reb says air pressure is biggest factor and you have control over it.
Sure it won't be as smooth but if your tyre placard says 30 then 40psi will make a significant difference and lower fuel use.
For same reason as a thinner tyre of same style will have less rolling resistance than fatter (assumes air pressure adjused on each for same tyre load rating)
Same applies to trailer tyres.
The lower rolling resistant tyres are designed to minimize energy loss in bending rubber, e.g. one factor is thinner is easier to bend.