The last few years I've found myself having low-grade asthma at this time of year when people start using their stoves, when previously it was linked to hayfever for me. Generally people seem to start getting bored of them by the new year and it clears up. Barbecues and firepits can be a similar problem in the summer, more so in still weather when there's no breeze to break it up. I get the impression that plenty of people also use firelighters as that can be quite a noticeable smell at times. That said, you could make the same argument about street food and all the farmers markets and pop-up food villages on recent years. If you have to change trains southbound at P Rye in the evenings, for example, the smell can be really strong. Spitalfields is another one.