Morality is another social construct, so like you said, do things that don't make you feel guilty. If you can go home and sleep in peace after seeing somebody jump off the cliff, why not? I don't see anything wrong with that.
Society won't forgive you, though. It is funny that we can be total assholes as individuals - and even create groups of such - but society as a whole has its own consciousness and moral standards that you'll be judged on. Even by the hypocritical jerks that would themselves walk away from a drowning person just like you. =)
Ah, life. What an ugly beauty.
On that note, you might be interested in joining us at @steemdeepthink if you haven't already. Thanks!