A number of countries subsidize the cost of gas domestically to make it less expensive for people. But that isn't a good idea. Governments need to accept the market price of gas, even add taxes, in order to reduce our dependence on it and become more effective and efficient energy-wise.
A number of prices come into play. The international market determines the price of crude oil, and the fact that the process of extracting oil today is more expensive than it was 20 years ago has an effect on that price. Environmental impacts also have to be taken into account, and taxes are a way to address them. That's the government's job, as Mr. Leach was saying earlier.