This is not easy because it is easy to change people's minds, but because once people change their minds they will not regret the loss of their old way of thinking. White makes one more point that I think is very important but rarely discussed. That point is that, in reality, we are a technological civilization and we are pleased by our technology because it makes life easier. We cannot romaniticize about what the world would be like if we were not as we are - this only takes our minds off of the tasks at hand. We must accept the reality of our lives as they are and change our views of the world in order that our technology does not prevent us from being aware of Nature and the consequences of all of our actions upon the environment.
People can make changes to their environment regardless of the amount of leisure time they have.
Every day you impact the environment. Driving to work creates pollutants. Eating food causes deforistation. It's how YOU plan your day to minimize environmental impact. Activism is not the only way to be an environmentalist by any means.