I think with all the improvements made in the past 30 years regarding engine emissions, oil pollution is now largely a myth.
It still exists and always will.
The question at hand though relates to the fundamental assumptions of the global warming crowd... things like the notion that water vapor is by far and away the single largest factor in the GHG equation, but it's kinda tough to implement a financial penalty or get the willfully ignorant all up in arms over water... The solution is to highly exaggerate or outright manufacture a villian to arouse the low-info demographic into action
Enter carbon (CO2)... This is an easier target as the marketing dept can associate that with pollution/emissions but once again, the willfully ignorant decide to ignore the reality that we (as are most life forms on Earth) are - wait for it - carbon based.
This is not to suggest that conservation and anti pollution measures aren't of great value, but your run-of-the-mill ecotard finds it convenient to flip from one to the other when they are shown the factual evidence.