Ray Kroc, McDonald's founder, insisted on __________, which became a competitive advantage for this firm?

By 1960, there were more than 200 McDonald's outlets across the country, a rapid expansion fueled by low franchising fees. Ray Kroc had created one of the most compelling brands of all time. But he was barely turning a profit. Ultimately, it was his decision to use real estate as a financial lever that made McDonald's a viable operation. In 1956, Kroc set up the Franchise Realty Corporation, buying up tracts of land and acting as a landlord to eager franchisees. With this step, McDonald's began to generate real income, and the company took off.

So the answer is:- 'using real estate as a financial lever'.

Absolutely -- and no. Religion certainly gives a "competitive advantage" to groups, whether it's a clan, society or culture. Religion became prevalent in early societies as a way for people to explain things that they couldn't understand otherwise. To use your example, why would one berry be poisonous while other berries are nutritious? Someone without knowledge of botany and chemistry would have no idea. So, enter an invisible, higher power which somehow dictated everything about the world. This mythology certainly took hold and was passed orally, as you say. Groups that stuck together and shared this tradition created a system of norms and mores which translated into a more orderly society than those groups who did not. It goes without saying that cohesion and organization is an advantage to a society. Furthermore, as religion evolved it became a source of inspiration. If a people believe they are fighting, working, suffering for a higher purpose (such as a God, "freedom", etc.) then the people are much more willing to do the hard work needed to achieve the goals of the society. This is evident throughout history and is still happening in today's world. Therefore, using religion as a "competitive advantage" has not outgrown its usefulness. Religion is still a major motivator, in war, obedience to a state, convincing the masses not to question misery, uniting a nation against another and so on. The US has no central religion, which is way you see other abstract concepts hailed as a rallying cry, like "Fight for our freedom," "patriotism," and others. As long as there are people in this world who dislike other people, religion will be around.

In addition to what the other two answerers said, he also demanded that his restaurants be very clean. He made sure that all his locations were kept very tidy.

The Hamburgler managing assets and quality control, among other things.

Treating workers like scum while squeezing every moment of work from them and not paying a fair wage or benefits.

product consistency (making all hamburgers at all his restaurants look and taste exactly the same with no variations for local preferences)

I would also say uniformity (same napkins, cups, straws,,,,,)

consistency