Title/Designation

A thought came into my mind that why titles/designations in Government are same as in organizations. I mean the titles used in governments should be different from companies/organizations. Say for example President, I am Ok with country having a President or Vice President. But why these titles are used in organizations. President or Prime Minister is a Head of the country and President in companies is not the Head. Though most of the CEOs are also President. Then why using President and Vice President in companies

I am totally against using Presidents and Vice Presidents titles in companies. An alternative can be Managing Director.