I agree with nearly everything you say, and I say "nearly everything" only because I wasn't reading closely, not because I disagree. The problem is that everyone here is fully willing and able to have a nuanced discussion about eating meat, but we're having this discussion because one person insisted on having a binary discussion about eating meat. It's gonna be challenging for anyone to learn anything from anyone else because most of us agree on the gray area and we aren't committed enough to convince or be convinced as to its shade.
The consensus is therefore in the superstructure: we agree that we're not absolutists, so we reject the polarizing process as a means to discussion. Too bad we aren't in an actual room. This would be the moment when a bunch of us look at each other, get up, and go to a brew pub. Instead it's quarter after 2 on a Tuesday and I think the closest person to me is around 15 miles away. Thus I'm off to do something constructive in my company's lab.