Marco Mayeux, 42, the bartender of Le Relais, a Paris cafe in the 18th Arrondissement, said the ban alone had cut his coffee and bar business by 20 percent.

Image Nathalie Guérin opened her cafe in Saulieu two years ago, but this summer business started to droop. Its been in free fall, she said. Credit... J.B. Russell for The New York Times

“A place like mine doesn’t appeal to everyone; it’s very working-stiff,” he said. “There is a coffee-at-the-counter feel that isn’t attractive anymore.”

Before, clients would go inside a cafe, have a coffee, a cigarette and another coffee. But now they go out to smoke, and sometimes they do not come back, many cafe owners said.

Gérard Renaud, 57, owner of the Restaurant de L’Église in Marsannay-la-Côte, said that business was down at least 30 percent. “Now people don’t eat,” he said. “They come in for a coffee or a little aperitif and that is it. We are used to being busy, but now we feel lazy, and it is depressing.”

Ms. Guérin is trying to sell her cafe, but has had only one nibble in this lovely town of some 3,000 people, much visited by tourists, where the renowned hotel-restaurant Relais Bernard Loiseau is just down the street.

Jean-Louis Humbert is the district director of the Federation of Cafes, Brasseries and Discotheques, and he is blunt about Ms. Guérin’s chances. “It’s finished for her,” he said. “No one wants to buy it. The banks don’t want to lend her any more money, and it will end up in liquidation.”

Daniel Perrey, 57, owner of the Café du Crucifix in Crimolois, blamed social change, saying: “Sadly, it is the end to a way of life. The culture is changing, and we feel it.”