In lakes, or oceans, seas…water first goes underground and help plants to grow up. Then, water evaporates and forms clouds, which are pushed by wind until it rains over. Here we got an example of rain in top of a glacier, and water is transformed in ice, which smelt and go back to the river its first belong to.
See the difference ? The people who are consuming most of water are the richest. But how could poorest countries develop themselves without water ? And how could people survive without drinking water ?
This is the reason why there is a frontier between Northern countries and Southern countries. A frontier that we choose to draw long time ago.