Shoban this may be compared to the water of the river and the water of the tap .
Your reasoning is perfect . It remains the pleasure in some cases  to go outside in a forest for instance , the pleasure to be in " nature "
 In friendship
Michel

@dianelub - Diane: Don't take my posting too seriously, but in that case people can say, "I want to enjoy the sunshine outside", or "I want to feel the breeze on my face". Why use the word "fresh air"? And wherever you live, pollen and dust is everywhere. And if you live in America, which I know you do, gases from car exhausts is everywhere. If you have factories/industries within a 10-mile radius, industrial fumes are present in your air. The town of Mathura is about 30 miles away from Agra where Taj Mahal is situated. Do you know industrial fumes of Mathura has turned the white marble of Taj Mahal yellowish, and it is still doing the damage? Scientists from all over the world has determined there is no way of preventing this, but to shut down the factories. And this, of course, is not possible because of political reasons. LOL.

-- Shoban

@fauquet - Then say, "I want to enjoy nature" (don't say nature is calling me)! Why say, "Fresh air"? Talking about water, I never drink spring water (and waste my money). Spring water (including your Evian water) comes from nature. That means, all the animal wastes, birds' droppings, soil, dust, rotten leaves and stems/twigs of trees, and so forth have contaminated the water. Only stupids drink them and pay for them. I drink the filtered and treated water supplied by my city's waterworks. For additional safety I use Brita water filter and filter it again at home. When I hear about outbreak of waterborne diseases in nearby areas, I also BOIL my water before drinking. You know, I am smart, real smart! LOL.

Your friend,
Shoban