Having lived in the UK, I would point out that the $8 plus price per gallon is only valid if you are a visitor and earn you money in dollars or some other currency. If you are a UK resident, you earn and pay for your petrol in sterling not dollars. Another way to think about it is that if I earned my money in the UK and bought gasoline in the US at $4 a gallon with the exchange rate at 2:1 that makes it equal to ~$2 gallon if gasoline in the US were at $4 a gallon, but only for that person. It would still be $4 a gallon for all the rest of us. So while petrol is basically more expensive in the UK than in the US due to higher taxes on fuel, lets keep the differences in perspective.