Well, dams are really the product of many people, but civil engineers are usually key players. Keep your eye out for this cee symbol to point out things that civil engineers do. An obvious example of a societal structure is a bridge. A bridge provides a large number of people with a convientient way to cross a river. We see that societal structures are necessary on a daily basis.
People are willing to deal with traffic and road construction in order to use their roads.
Societal structures are built for specific reasons to help people.