There are many reasons and benefits to fasting. Some are spiritual and some of social nature. One of the social dimensions of fasting is that when Muslims fast during the daytime of that month of Ramadan, they are hungry. And during that period of hunger, they (particularly the rich) can relate more to the suffering of the hungry and the poor people in the community and around the world. Those who fast during the day-time, know that after sunset, there will be a meal on their dining table; but they also realize, or should realize, that there are many people who fast even when it is not Ramadan, and they fast without the assurance of having a meal on their table at the end of the day!
God desired that His servants may be equal on this occasion and the rich may also feel the hunger.

This realization stimulates the element of charity and sharing in us. In this sense, the month of Ramadan is also a month of sharing and charity. At the end of the fasting month, Muslims have a major feast known as Eid-ul-Fitr when they gather in the mosques for special prayers and celebrations. However, before Muslims go for the special prayers, they are required to pay a special charity. This is like a first step which God is helping us to take on the path of charity and sharing with the hope that Muslims will continue to share what God has given to them with the less fortunate members of the society.

Reference: Fasting in Ramadhan: A Simple Guide To Ritual, Social & Spiritual Dimensions, Sayyid Muhammad Rizvi)