Thinking is expensive.
Structures (like families, disciplines, communities, and institutions) keep us from having to re-derive our values with each new decision.
They take the hard-won lessons of the past, and turn them into pre-determined axioms of the present.
This is somewhat restrictive, and can give rise to corruption. But the alternative (zero structure and complete reliance on cognitive horsepower) is enough to drive anybody insane.
Which still leaves the problem: which constraints to adopt?