Why did avatar give off a big environmental message?

Answer 1

There are two main reasons:

1. Many traditional cultures destroyed by invaders have had very close connections to the planet and/or the environment, for example the American Indians, the Australian Aborigines, etc. It is a well known cliche that the invading forces have absolutely no care factor for the native way of life or their protection of their local environment. Also, many tribal cultures already have as part of their culture protection of the environment as it helps their way of life stay sustainable
2. The other reason is that people in Hollywood are very liberal and often try and draw the masses attention to the problems of the world, such as how much we are destroying the environment. They feel if they have the power to reach that many people they should at least send a message as well.