The reason demand hasn't gone down for oil based products is likely due to our terrible transit and inflated housing prices. Believe me, most people I know would prefer to ditch our cars and high insurance prices, but we don't want to ride a bus for 3 hours just to get to work. There's no affordable living near our jobs or main transit lines so we are forced to drive and consume highly taxed gasoline. However, that is not to say a cabon tax wouldn't work better across Canada where they have transit systems more capable of getting people to work / school.