I agree. Attempting to tax something in the name of saving the planet is as effective as constantly raising taxes on cigarettes to cut health care costs. Instead of wasting our time and money in trying to collect taxes on free-floating gas in a way to decrease our desire to have beef, why not try to develop a process to collect the gas and use it as a source of fuel. That would have a greater impact on helping the environment than taxes.
You confuse the roles of the U.S. government and the private sector here. When an industrial activity produces a negative externality - a cost to society - it is the government's role to try to tax that industry so that it produces less, thus produces a smaller cost to society. It is the role of the private sector to come up with profit-making processes like the one you suggest.
And cigarette consumption has dropped dramatically in recent years. Higher taxes, along with other factors such as anti-tobacco campaigns, have had the effect of causing fewer people to smoke. That's the primary effect of taxing something.