The world's oceans are over-fished. It takes more land resources to bring animals to slaughter than it does to grow vegetables that could feed the world. What may be pleasurable, or even good for the individual is not necessarily what is good for the 'common' -- for the majority of the people who will have to live on a planet being depleted of natural resources. This is also true for car-buying habits. When the price of gas goes up, there is often a shift to purchasing more fuel-efficient cars. However, as the price of gas goes down, particularly in the United States, the trend for larger, showier and more fashionable cars tends to increase. People are also loath to take public transportation, except in cities notable for their congestion and good public transportation systems like New York City. Personal self-interest in saving money cannot be relied upon to change car-buying habits in a meaningful way to create real changes for the environment, nor can changes in eating habits. People have enough trouble limiting their consumption simply to lose weight,...

This is why there is a necessity for the government to pressure people to change their behavior with carrots and, if necessary, sticks. Neither good will to others not self-interest can be relied upon to change personal behavior. Individual behavior has a collective impact and must be regulated with fuel efficiency standards and limits upon how much land our agricultural industry can use to raise meat. Fishing must be heavily regulated. These may result in a short-term loss of pleasure for the current residents of planet Earth, but they are necessary for the long-term well being of the environment.
Works Cited

Bittman, Mark. "Re-thinking the meat guzzler." The New York Times. January 27, 2008.

[October 4, 2011] http://www.nytimes.com/2008/01/27/weekinreview/27bittman.html

Brehm B.J. & D.A. D'Alessio. "Benefits of high-protein weight loss diets: enough evidence for practice? Current Opinion Endocrinal Diabetes Obesity, 15.5 (October 2008):