We tend to think that if we do a good deed, a blessing in disguise is going to return to us as an answer to what we did. But things do not always go as planned. Nice people do not get what they deserve in real life. Not always at least.
But, what happens when the deed in question is actually evil? To my experience, even though goodness is not always returned, maltreatment does. So, the moral of life in this case would be. Strive to be good, because being bad is not going to lead you to any place good.