My comment is that due to lack of education, guidance, and general intelligence, most people don't really know what makes them happy. They think that feeding the beast of greed and envy will make them happy, but it won't. Keeping such things ever at the forefront in my own life I consider my life well balanced. I'll never have as much money as plenty of people, and will continue to live happier than them with a less regretful life as well. Family, principles, health, etc. are not at all benefitted by basic objects and the constant winless search of property. Many never figure this out, so their lives are never as fulfilling as they could be.
Oh, and in regards to the earth? Well, the planet has finite resources. Clearly the human race will eat the planet up and spit it out, much as Agent Smith concludes in the Matrix (referring to humanity as a virus). He's quite correct. The question is how long can we go... I mean truly there's just no hope for mankind's longevity. Short of divine intervention, or the timely discovery and execution of interplanetary colonization the human race will kill itself, or at the very least bring itself to its knees eventually - all it's own undoing. The few who can forsee it are just not strong enough to fight the will of the consuming many.