How is anything gained by a funeral protest, under any circumstances?
Wel, wat if you'r a powerful political figure who's using your power to assassinate people left and right, and your son gets caught in the crossfire. A group of protesters gather at the funeral to educate the public, they bring documented evidence to feed the media proving you'r a corrupt murdering politician AND your son got caught in the crossfire, and the fact that the protest is happening at a funeral attracts so much attention somebody steps in and helps.
Now, all that's not very likely.... but anything can happened and what will be can't always be guessed.
Next, the "Absolute Truth" argument. For God to present Absolute Truth, God has to somehow prove the Truth to be Absolute - That means God has to find a way to communicate something much of modern thinking considers absolutely impossible.
Say God presents a perfect moral code. Fine, but in order to be justified in listening to this perfect moral code, wouldn't God have to prove the moral code is perfect? Or otherwise prove God not only exists but is also perfect?
In order for God to communicate such a thing, God might inject the Perfect Truth into the believer's head --- in which case the Believer might temporarily or permanently gain insight into every angle, cover every single reason why the perfect moral code is flawless. God wouldn't necessarily have to violate free will to do this. Simply exercise your free will, and ask for that Perfect Truth.
That's what I did. As a very young child, I said, "God, give me the truth, whatever it costs me." The closest I got to the truth was the conclusion that, You process logic as objectively as you can and weigh the evidence, and act based on what that evidence tells you is the way to act. You can't absolutely prove anything for many reasons, one being it's always possible a fallible human missed something, but you can lean on the evidence, and change how you lean as new evidence is introduced.
As to the question about why it is helpful to support Greatest Overall Freedom, the answer for me is that providing freedom prevents pain and promotes enjoyment of life, and enjoyment of life is what makes life taste worth living. Taking away freedom is a symbolic surrender of the same measure of your own freedom, unless you can somehow demonstrate (to yourself, if nobody else) that by doing so you'r actually preventing the loss of more freedom than you'r creating.
If you take a certain measure of freedom, your environment gains the right to defend itself and you lose the right to the measure of freedom you'v taken. If you present a situation that risks taking more freedom that what you actually intend, your environment gains the right (due to the evidence it is forced to consider) to defend itself by taking that amount of freedom or less... For instance, if you hold a gun to somebody's head and say, "I'm going to shoot you in ten seconds. 1, 2, 3..." Somebody has the right to kill you even if you'r just joking, because you'r risking somebody else's life.
On the other hand, if there's an equal-risk plan that requires less interference, for instance if there is a way to remove the gun from your hand without risking it going off, then that method of defense is superior, because more freedom (and happiness) is supported.