I think it pretty much says it all about trolley problems, though. Why are they so popular in ethics? In part because they are so sanitized and sterilized and you don't have to be haunted by them. It's connected to the fact that the Fat Man who shows up in a number of variations ends up being dropped on train tracks, blown up, etc.: it's cartoon ethics.
I tell you true: you will know the stories and scenarios from which you may genuinely learn about ethics and moral life from the fact that they seize you and will not let go -- for they are the ones you cannot manipulate and gloss as you please.