Except, a single McDonalds can serve ~5 orders a minute. Yet, a car dealership that can sell 2 cars a day is doing Ok. Let's assume 2 cars a day over 5 years = 3,650people before you get repeat customers. (Average salesman sells 7 cars a month * 8 sales guys.)

Edit: http://www.bluemaumau.org/6057/ten_largest_restaurant_franch... 2 million / store per year / 52 weeks / 6$ a meal = 6,410 people averaging 1 vist a week per McDonalds.