This is why I get so disturbed by all of the vapers who say they won't even bother with such people...
That guy would've continued going around ranting his nonsense, potentially discouraging many people from trying electronic cigarettes.
Now, after being given a healthy dose of "shut the hell up" he may just decide that he should shut the hell up.
And if you believe in miracles, it might have even changed his mind.
When people make wildly inaccurate statements, on any topic, they should be called out on it. I've never been a great believer in the idea that one should let BS go unchallenged in the name of politeness or civility. There's nothing impolite or uncivil about correcting someone who's wrong. It doesn't have to be done loudly, or brashly, or with the intent to embarrass, but it should be done nonetheless.