Here's a scenario that requires governing:
In a Libertarian age an enthusiastic and optimistic young man get an idea he believes will make him rich. He implements it. He offers this culinary sensation to the public. They try it. Success... at first. but as the days go by his customers fall ill. It is discovered that they have been poisoned. And the cause, ignorance, without sanitation instructions or requirements our erstwhile entrepreneur did not realize what was required to keep invisible germs at bay.