I mentioned once before that the last time I was in Paris I vowed never to return until smoking was no longer allowed in hotels, restaurants, bars and cafes. Fortunately the law has gone into effect and shock of all shocks, people actually paid attention.
Of course, the French government had a many year propaganda campaign on television and signs about the horrors that cigarettes would do to the adults and especially to their children. One ad on television was a car with mother, father and two children and the adults were smoking, It showed the car foggy with smoke and then explained the horrible things that smoke was doing to their children's health and well being.
However, that doesn't mean that Parisians have given up smoking, nor have they given up going to restaurants. So the restaurants must find ways to entice smokers to come to their local. The photo above is part of the answer. Outside of the restaurant there is a plastic room-like affair with tables. Now it cannot be a real room, because that would then mean it was part of the restaurant and smokers could not smoke, so over lapping plastic sheets are dropped down from awnings around the front of the restaurant or bistro. Natural gas overhead space heaters are going full blast to give some warmth, sometimes as many as ten are used. That will work as long as natural gas doesn't get more expensive. Or will the prices go up to cover the extra cost? Probably that will happen, or the government will subsidize the restaurateurs for the expense. Knowing the French it is probably already being done.