Some people don't want to have to smell the often very sickly smell of people vaping around them. Additionally, the large plumes of 'smoke'; create a safety problem in itself... Through both panic and the inability to distinguish between that 'smoke' and actual smoke from a fire. People should just obey the bloody rules and do as their told sometimes. When I used to smoke 30 Marlboro a day I still managed to fly long haul without it being a massive problem, so I'm sure the idiot on the aforementioned shot haul route should be able to manage the flight without vaping...