Comment by xg15

Well yes but morals and ethics are almost by definition about valuing the interaction between people. As such, even if you assume that moral is subjective, if you only have your own personal morality, that's rather useless - it only becomes useful if you can agree with some other people about common rules of behavior.

You could say for yourself "I personally don't believe in private property, so I don't see any objection with theft" but my hunch is that this argument wouldn't do much to calm the victim of your theft.

That proposed code of ethics in software seems like an attempt to create exactly such an agreement.