People study ethics in order to learn about morality, integrity, responsibility, conscience, dignity, respect, and honor, as well as to learn about the difference between right and wrong or good and evil. Ethics, as a field of moral philosophy, is essentially a system of moral principles and rules of behavior.
Civilizational progress and social and cultural growth and development cannot happen without the existence of ethics, as the people would mainly focus on self-growth and self-interest; this might not seem as such a bad thing, however, it's important to know if those interests are morally good or morally bad. If we focus only on ourselves and our own mindsets, we won't have the patience or the opportunity to see the points of view of other people and analyze their systems of beliefs and values in order to determine if we should praise them or criticize them. Most importantly, we won't be able to analyze or question our own personal beliefs, opinions, and choices, which in turn would make us narrow-minded at best and immoral, evil, and intolerant at worst.
Thus, it could be argued that studying ethics is inevitable; we need to have a way to determine whether or not our behavior is good or harmful, and we need to have a moral code which will guide us through life and help us make the right choices, both for ourselves and the society.
This is why ethics is so important in pretty much all social, cultural, economic, and political spheres; if the individual and/or collective mentality and system of values is "wrong" or "flawed," then we cannot move forward and live harmoniously and achieve great things, neither as individuals nor as a community.