Mr. Cazenave said he employed 22 people and respected all labor regulations, including the required two days off per week for his employees. But he ran afoul of a local decree from 1999 stipulating that shops selling bread must close for at least 24 hours every week. Mr. Cazenave’s case will be brought before an administrative court, and he could be subject to fines.

Mr. Cazenave said he opened the shop more than three years ago. “I’ve been open seven days a week since the beginning, knowing very well that I had this sword hanging over my head,” he said.

He said he was now closing his shop one day a week, hoping it would please the authorities. But closing one day a week could cost him up to 250,000 euros a year, he said, forcing him to fire several employees.

The rule is not a national law, but a majority of French regions have similar decrees, which are a result of negotiations within professions. In this case, its roots are in rules started in the early 20th century to protect bakers from being overworked and abused.

Bakers these days say the rules protect them from the competition of larger stores and chains.

“If there are no decrees like this, only the larger businesses can organize themselves to open seven days a week, and the smaller ones will be forced to,” said Jean-Louis Mack, the director of legal affairs at the National Confederation of Bakers and Pastry Chefs. “How are we going to attract young people like this? ‘Come join our profession; you will work nonstop, 24/7’?”