This verse is usually understood to mean that God provides for all living things, satisfying their wills and desires. Another interpretation is that God provides all living things with will; i.e. with desire, so that all living things should have desire.
When we say the Grace After Meals, we thank God for the food He provides for us; we do not give thanks for being hungry. However, if we talk with people who suffer with any of the diseases which cause loss of appetite, we will discover that we must be grateful for the sensation of hunger as well as for the means provided for us to satisfy that hunger.
This concept applies to wants of all sorts. An ancient Chinese curse goes, "May all of your wishes come true." Why is this a curse? Pause a moment and reflect. What would we do if all of our desires were fulfilled? Since sensation of needs cause actions, without any sensation we would have no motivation to act. Satisfaction of all our needs would essentially mean an end to life itself.
As a physician, I frequently encounter people who are very depressed and who have no appetite at all. Other patients have diseases that affect their digestive systems, so that they cannot even tolerate the sight of food (let alone crave it). We must remember, then, that when we feel the pangs of hunger and thirst, we should appreciate them.