Three problems:
- Others may not realise that the 'smoke' is not real and take it as smoking being accepted. You might think this a wild guess but we have all travelled regularly on public transport, or been in supermarkets where signs and information is ignored or willfully ignored.
- The batteries can be a problem. There are VERY cheap rechargeable units on sale via shops and online. No regulation required. The airlines are cautious about many things that can damage life. I would prefer not to have some cheap battery endanger my life.
- If people ignore the rule about using these devices - what other rules of the airline will they all ignore because they don't like them?
Yes, I'm a non-smoker.
Yes, I do understand addiction.
In the time since smoking was banned and before these items were invented - people survived. They used patches and pills and chewing gum.