You're talking in some absolutes here, but I don't think any of it is so set in stone. If a city vegan doesn't think about where his food comes from and isn't mentally bothered by this, then he's healthy. If a farm boy slaughters livestock casually isn't bothered by it, he too is healthy. Each are well adapted to their circumstance and is healthy so long as they remain in that condition. What other people think about either of them is the problem of those other people.
That pattern of reasoning is also used by people who defend hitting their children because "my parents hit me as a child and I turned out fine" when arguably the fact they think it's okay to hit their child demonstrates they're not fine.
Yes, there are people who aren't "bothered" by killing animals. There are also people who aren't "bothered" by killing people. I'm saying that's a bad thing. I live near an industrial slaughter house, in fact one of the biggest "meat factories" in Europe. The people who work there are not okay.
I'm not saying "don't eat meat". I'm saying if eating meat literally doesn't bother you, you should consider that a warning sign.
