I'll try to explain how I see ethics a bit more dude, see what you think, I'd be interested in hearing another perspective on non-action, and I think it's a really interesting thing to consider. I am not 100% sure of my approach, but it makes most sense to me at this time
The reasoning is behind the ethics of why it's wrong to kill an animal, not why it's right to not eat meat. If you try to explain why it's "right" to not eat meat, ultimately you are describing doing nothing, and you have to describe the problem, which is killing animals. To not eat animals in itself is neither good nor bad, it's just nothing. Promotion of veganism is the + because you can make others reduce their consumption, and without your input they would not have done so.
I think that taking action which causes harmful results is bad, and I think that taking action which has positive results is good. I think that taking no action at all is neither good nor bad. But the thing is that people should aim to be good, if you don't try to help people, you're nothing, you are not taking good action. So the analogy of standing by while someone is mugged - the mugger is performing the bad action, and the by-stander is taking no action, they are not to blame. But they are not "good" as a result, they have done nothing. Of course you can say that they should have helped, and that is correct. But, I don't think that the default is "good", and anything below that is "bad". If you were to score the mugger and the by-stander on some kind of ethics scale, where would you place them? I say that the mugger is in the red, the by-stander is on 0, and if someone helped out, then they get a + rating.
If the world was full of people who did nothing when something bad is happening, then there would be no prevention, and things would work out for the worse. But, those who did nothing are not responsible, they are just useless, at least that's how I see it. I aim to be a good person, not a useless person!
In a society where it is "wrong" to do nothing, do you arrest people who don't help people who are being mugged? What level of positive action or self-sacrifice is required to avoid legal action?
If someone is begging on the street, and you give them 1 dollar, you could give them 2. Are you wrong to give them nothing at all, are you wrong for just giving them 1 when you can give 2? and so on. On my scale, I say that giving nothing earns you no good points, and the more you give in relation to what you earn and can afford, earns you good points