Driving 'privalege' unconstitutional?

JoeSilva writes: If one accepts that the US Constitution affirms Government only has the powers that it's citizens grant it, then what is this claim by the states that driving is a privalage granted by them? There is certainly good cause to grant the government regulatory powers over the use of motor vehicles and over our rights of way, for the common welfare, but government claiming driving is a privalage it grants to it's citizens seems to me counter to our constitutional ideals. What say you?