The ability to tell stories is morally important; as far as roleplaying games train us in telling stories, they morally improve us. (This may not the only way they do so.)
An example: I just took the train from Leiden to Utrecht. At some point, an untidy looking guy comes into the part where I was sitting and starts rummaging through the litter bins in order to find some food. A little while later he starts asking me for food (which I did not have); eyed my bag hungrily, as if he were about to try and steal it; then suddenly vommited (or noisily spat, I didn't try to find out) on the floor and departed. The prominent thought in my mind was: "Get lost, junk."
However, I then realised that the scene I had just witnessed could be part of many a touching tale, the protagonist of which would be thoroughly human and sympathetic. A million things that I can emphasise with and understand could bring a man to this behaviour. By narrative imagination, I can construct the sketches of some on the fly. And so the prominent thought in my mind became: "What sad circumstances have reduced him to this? Will he ever get out?"
To see the other as an individual human, not a prototype; to think of what you observe of him as a moment in a long temporal chain instead of thinking of it as the essence of his being: that is part of what morality is. And you need narrative imagination for it; the ability to tell stories. Especially, the ability to tell stories about real human beings with their weak and pathetic moments. The best of our roleplaying games allow us to train this ability.
(Paul Czege once told me that one the things he wants with Acts of Evil is stimulate people to think of other humans as, well, good and noble human beings. He gave the example of a fat man ordering an extra large meal in a fast food bar. You could think: "Hey fatto, you'd better take a small meal or burst." Or you could think: "Well, maybe the guy has been working in his poor old mother's garden all day and is simply starved." The second needs a sharper and quicker imagination, but it surely is to be preferred.)