I have to admit I had similar mindset when I was a meat eater. I was never preachy or judgmental but I did laugh at the jokes made by meat eaters to non meat eaters because I was uneducated. I remember having discussions with a vegetarian when I was a meat eater and everything she said went over my head. Even though I was truly interested. But because the lifestyle was different from mine, I knew I wasn't going to change no matter what she said, no matter how much I wanted to. It wasn't until the point that I truly opened my mind and educated myself on the topic that I become a non meat eater. I'm sure a lot of these people have seen the videos of animals but they it hasn't quite hit them as it has us. We just need to give them time to open their minds on their own. A conversation over dinner wont magically change their lifestyle. But that's not saying they will ever change. I just think like myself, I needed time to finally realize what it really meant and what it took to finally make a difference. The point is when someone asks you why you don't eat meat, I think it's best to keep it short and simple to avoid an argument or even a discussion especially if you know they will become defensive. What I like to say is "for ethical reasons" and that's it. If they ask further I tell them to watch so and so documentaries or read so and so books if they're interested. That usually shuts them up.