It refers to a specific situation or event. ... Dramatic irony is when the audience knows a key piece of information that a performer on stage does not
To capture the audience's attention and show that he cares and is addressing his speech toward them.
Answer:
There is dramatic irony in Macbeth's speech in the royal banquet scene, as well as in his conversation with Banquo's ghost. There is much irony in Duncan's speeches as well, when he greets Macbeth as 'O worthiest cousin', his words prove ironical because Macbeth commits the most treacherous act by murdering him.
Explanation:
I think it was when they started the point of telling stories of the witches and what they did with the people it just started to spook them out and they feared that maybe they were honestly true. And I think at that time it really wasn't the best time to stand out and/or say/do something out of their league because they would think you were a witch.
(And we all saw Sleepy Hollow sooo) :)