And many different human ethical systems exist. If you believe that eating animals is always unethical, that is your ethic. If that means you believe I am unethical, then that viewpoint is valid within your system of ethics.

Sorry, but that is just a very poor try of avoiding the argument. What you say here is basically true, because if I move to other countries, I can do bad things that are under their umbrella of "local ethics". Like moving somewhere east where women are still seen as property and where I can abuse them.

Does that mean that we cannot challange "local ethics"? No. You can challange any ethical standpoint. And you should.

But you avoid the core argument by stating empty phrases like the one above :/

the only way to change a person’s ethics is to appeal to them by showing the commonalities between belief systems, then showing them the benefits of certain variations that you believe.

In this case I can simply use logic. Logic shows that there is no justification for the suffering and deaths of all these innocent animals as long as there is no necessity for that. Don't believe me? Try to justificate it right now :)

Neither you nor I like animal suffering. The difference is, I’ve seen plenty of animals lead relaxed, happy lives, that end painlessly before the animal is turned into meat. I understand that the notion repulses you.

I grew up with many animals that all had to die. I saw how they died, with pain and without pain. But the difference is that, even though I was tought that this "is OK", I challanged this belief system, which is quite easy. And the main difference between me and other people is that I accept if I'm wrong, I do admit that and, after this first step, I change things.

I saw that it's wrong to just consume and not give a fuck about the environment. That's why I'm changing a lot even though it's highly uncomfortable at times.

I saw that it's wrong to judge people. So I stopped that

I saw that it's wrong to pay for animals to suffer and die, when there is no necessity to do so. That's why I started a vegan lifestyle

You kind of explained your viewpoint, but you didn't say anything constructive in regard to the arguments. So it's nice that you try to explain your viewpoint, that's something I really appriciate, but you should atleast try to state some arguments to the arguments that have been told. Right?