Most people have no idea about the energy density of modern liquid fuels and how that affects their everyday lives. And what it might mean not to have any.
I don’t think we ever have to worry about not having any. Even if we run out of petroleum, we can always distill alcohol as long as there are some plants around. Not as good as gasoline, but at least we would still have some kind of fuel available.
If there are no plants around to distill, well, we’ll probably be dead, so who cares?