People who sit in the car with the engine running waiting, for long periods of time, when it’s not cold outside.
Just burning carbon and polluting the air for fun.
Worst of all are coach drivers. Those who walk around for 20 minutes before the bus is due leave talking to colleagues and usually smoking, with the engine running the whole time. Like it’s the 50s still when you might not risk turning the engine off in case you couldn’t restart. Morans.