On Earth there is a clear space between the ground and the cloud base. This phenomenon is not confined to Earth, it's the same on Venus, Mars and Titan (moon of Saturn).
Is there a law of physics which inhibits the formation of cloud at ground level?
Living in UK I know that ground fogs occur very occasionally, generally not lasting for more than a few hours, and for all we know it might be the same on the other planets, but it is not the normal state of affairs on the bodies mentioned above.