Telling people about the logical fallacy of generalization from fictional evidence doesn't make it go away; people may just go on generalizing from the story as though they had actually seen it happen.

That danger can be minimized in an elegant way: by referring people to a story that shows one shouldn't generalize from fictional evidence.

The more likely they are to inappropriately take the messages of stories to heart, the more they will be to take to heart the message not to do that.