[ghaff]

>leaving the vast majority of expense in deprecation and maintenence.

Depending on the car, gas is probably between about 20% and a third of a car's operating costs (which are typically in the 30 cent to 60 cent per mile range). Although there are a few vehicle costs, like excise taxes, that are more or less independent of distance driven, most car expenses will scale with mileage--especially in regions where rust isn't a major issue.