One of the points of engaging in extensive debate about systems of morality is that while doing so you have the opportunity to influence the way your community thinks about how people should behave. This allows you to gain practical advantages for yourself and cause harm to your rivals.
I disagree your original claim that gaining advantage is the point of engaging
in moral debate. Your revised claim, that it is only one of the points, is uninteresting, since any tool can be misused.
I disagree your original claim that gaining advantage is the point of engaging in moral debate. Your revised claim, that it is only one of the points, is uninteresting, since any tool can be misused.