Even 100 years ago the global population was only 1 billion - a footprint the biosphere can manage, and there were no cars on the road. Today there are about 6.5 billion people and over 1 billion cars! 100 years ago sweets were a luxury to be appreciated, today they are mass-produced confectioneries whose wrappers litter byways.
While we are limited by human needs and desires, we need to keep our world in mind when we make decisions.
As individuals it does not seem to matter whether we care about the environment or not. We grow up thinking that the earth is deep, the seas are huge and the air extends forever. Dropping that wrapper or old bottle by the side of the road doesn't matter because it will be taken care of and anyway my friends do it.
Most species are conscious of what they do with their waste. Somehow they know that polluting the river that they drink from is not going to do them any good. Modern society seems oblivious to this. Perhaps because our populations and technology are growing, we have more important, exciting and economically rewarding issues in mind. (Native or aboriginal populations, which are stable, do, however, work with nature to keep a balance.)
We are now recognising the need and the rewards of working within the balance of nature. Until people beelieve that green is more important than gold, looking after the environment won't be the most economic course. But people do care and with increasing awareness of the damage we do to ourselves, increasing technology (which makes green options easier and cheaper) people are deciding that green is more important than gold. To extrapolate to the absurd, we would rather live in a garden than in a room made of gold. Spend a little time and resources on tipping the scales in favour of nature. Flow with nature instead of against it.
Don't forget to turn off the lights!