A professional and experienced crew would have anticipated this very common issue. Airlines are fine to sell tickets to retards (which by the way are paying your salaries). Crews are used to show how to fasten and unfasten seat belts which for many of us look basic. Why explaining this smoke issue would be unacceptable ?
Crews are paid to carry out commercial operations, including services. The captain is responsible of this. It's part of professional crews to anticipate this kind of issue which is not new. Failure to do so can lead to such situations, but there is no point to blame passengers sincerely scared the **** out of their pants. This has nothing to do with those damn drunk tourists enjoying low costs flights to have booze and cheap girls and which would deserve to be banned for trying to open the doors in flight.
When you know passengers might be scared by the smoke, isn't it normal to inform them ? If not you are the retard. If you don't even know they might be scared, you're even more a retard.
Next time I will calm down a vapor scared passenger sitting next to me I'll send the bill to the airline since the crew missed it...