There used to be some sort of triffid growing in a large pot by the Terrace emergency exit, and I occasionally could sniff out butts that were half buried under the pebbles there. This is going back quite a few years, when the usual complaint in this forum was how difficult it was to get service on the Terrace. Well I'd say that service on the Terrace is much better these days, and the chances of a crafty illegal smoke now are very low. Anyone caught probably won't be flying BA that day, I would suggest.