As far as gas prices - be it a U.S. gallon or a litre here - the taxes charged by government are a fraction of the total price. Say 10-15% of the total price, at least here in North America. The rest is profit taking by the powerful oil industry. Many Canadian motorists were outraged when gasoline went from 90 cents a litre to $1.30 a litre after Rita and Katrina. They asked, and rightly so: "what the hell does a hurricane 2,000 miles away have to do with the price of gas here?" Last time I checked, Canada was a huge net exporter of energy. Those 2 hurricanes were a great excuse to make a few extra billion. Didn't you find it ironic that when the oil company executives went through that charade of "investigating" the high fuel prices, that the price of a gallon of gas magically went back down? I really could care less if the high price of fuel is being caused by environmental concerns, needed funding for public transportation, increased global demand, that we're actually running out, or that the oil industry is bending us over in true Capitalist Robber Baron fashion, whatever. It's still prudent to ditch the gas guzzling SUV and drive something economical. The price of fuel will also follow a "ratchet effect" where it increases easily, but lowers quite slowly, with the new setpoint always higher than the old high price. Folks around here screamed 2 years ago when gasoline went past 70 cents a litre, claiming they'd go broke commutting. Now it's 95 cents a litre, and they're doing without to feed the beast.
I think that the big oil boys will still have to have their super large profits. After all, once you become use to a certain lifestyle, it is hard to downsize. They will do the same thing that the power companies did when we had the "fuel shortage" several years ago. They just added a fuel charge onto the bill. There was no reward for conserveing.