“In the last seven years, I managed to take only three trips with my wife,” he said over the weekend. “Even back then, I was preoccupied with store operations, worrying about sudden cancellation by part-time workers. I had to hold a mobile phone while I soaked in a spa.”

The clash drew renewed attention last month when Mr. Matsumoto declared his intention to close his store on New Year’s Day, Japan’s most important holiday. Days later, 7-Eleven threatened to close his store.

When Mr. Matsumoto reopened on Jan. 2, the threat appeared to have been carried out. The company’s vast and super-efficient logistics system had stopped sending fresh supplies. The sales terminal where employees ring up goods is still online, but little else appears to be connected to the 7-Eleven apparatus that runs nearly 40 percent of Japan’s convenience stores.

Mr. Matsumoto says he still has business. Supportive customers have shown up to shop among his remaining inventory, which includes snacks, instant noodles, stationery items, detergents and cosmetics.

One of them, Hiroshi Nakayama, a 45-year-old electrical equipment wholesaler, had long watched the fight between Mr. Matsumoto and 7-Eleven and went to the store after his son’s soccer game to check in. The whole fight could have been avoided, he said.

“There must have been other solutions to fix the bad relationship with the company,” said Mr. Nakayama, who turned up on Saturday after Mr. Matsumoto, running on a skeleton staff, had closed for the night. “They could have discussed it more. It’s both sides’ fault.”