Final answer:
Without additional context, it is not possible to accurately state the distinction Sandel is using Sam's Mobile Auto Repair story to illustrate, as Michael Sandel's works cover a variety of philosophical themes.
Step-by-step explanation:
The story about Sam's Mobile Auto Repair does not have enough context provided in the question to accurately determine the distinction Sandel is illustrating. Typically, Michael Sandel, a well-known political philosopher, uses real-life scenarios to underline important philosophical distinctions in his works such as Justice: What's the Right Thing to Do? One common theme he might explore is the moral limits of markets, but without more specific information on how Sam's Mobile Auto Repair is used in Sandel's argument, it's impossible to provide a factual answer to what exact distinction is being illustrated.