I’ve been a vegetarian for about seven years. It started as an experiment, something that “just to see if I could.” The experiment was predicated by the reading I was doing at the time; my interest in philosophy (which would ultimately become my minor during my undergrad) led to reading several books on the ethics of food. Peter Singer’s work was the most influential on me.
I won’t go into my reasons for not eating meat beyond that: for me, it’s a point of philosophical consideration and what I perceive to be my own personal ethical imperative. It’s important for me to point out that I don’t feel the need to force the world to follow my own philosophical and ethical models. In fact, the only reasons I’ll ever talk about my vegetarianism (aside from on my blog, where I can talk about whatever I damn well please) is because somebody asks or because it’s polite to inform others of one’s dietary restrictions should you be planning a dinner or food-related social engagement. Usually, the latter reason leads to the former as people inevitably ask questions, usually of the “wow, what’s that like” variety.
Personally, I don’t really care what foods others are sticking in their respective pie-holes. My choices work for me and my innate iconoclastic tendency means I can understand why a person would get upset by being told not to eat the foods he or she wishes to eat.
However.
There’s an unfortunate side-effect of the fact that the vegetarians, vegans, and other animal-rights folks are the most vocal supporters of food ethics. The side-effect is a sort of “rejection by association.” Basically, if a person decides that he or she hates those preachy vegetarians and vegans, or thinks they are all liberal fruitcakes, or feminist gender traitors, or whatever, that person is going to dismiss the idea of food ethics out of hand. And that is something that I think is wrong.
Here’s a great introduction to food ethics that doesn’t come packaged with a “vegetarianism is great” side dish.
To wit, I don’t care if you eat meat. It’s your choice. But I do think that you have, or at least you should have, the same moral imperative to reduce suffering in the world. This is my basic humanitarian ethic that I think all people, regardless of background, should work to uphold.
So, go ahead and eat meat! Eat a delicious steak. Have two. But do so recognizing that not all steaks were created equally. A steak that came from a factory farm created much more suffering in the world than the steak that came from your local farmer’s market.
This is why I’ve said the decision to eat meat is a philosophical one. The attitude you have with regards to your food matters. If meat is consumed in a serious, sober manner, if it is done with respect to the cost to the life that was taken, you are justified in my book. If you raise your own animals or if you hunt and butcher your own animals or if you take the time and effort to research which companies produce meat with minimal suffering, you have my support. You are meeting this basic ethical imperative.
Be a carnivore if you wish. Just be an ethical one. No, more than that; realize that this is all part of the consideration that goes into being an ethical person. I think ethics are something that have fallen out of the social consciousness; we’ve replaced ethics with religion in most circles, which aren’t the same thing in the slightest.
Cynical Idealism 
If there’s one reason I’m happy to be in Central PA, it’s that I can actually get good food from local farms or from the university’s agriculture program. The meat tastes much better, and the fact that it’s more responsibly raised is a very nice bonus. Animal cruelty isn’t cool, and I wish it was easier to know just what happens to our food before it ends up on our plate.
That said, I’m always a little worried when I hear people preach against “modern farming practices” or any other phrasing that implies that the new way of doing things is inherently wrong. GMO products are a great example; you have a lot of people up-in-arms about genetically modified produce, but GMO products might be the only way we’ll ever feed our rising population off the fertile land we have available.
I have a feeling the answer is that we eventually produce less meat, and that the meat we do produce comes from places where we couldn’t really grow crops if we wanted to. Meat would be much more expensive as a result. But thinking historically and globally, eating a big hunk of meat at every meal isn’t really normal or necessary for the vast majority of the population.
What I don’t think is the answer are all of the “sustainable farming” natural micro-ecosystem things. Usually they’re some flavor of community owned shared resource. I’ve seen these bandied about a lot recently, and when you look at the food/acre, they just can’t support populations like we need in this modern world. GMO produce, along with revamped farming techniques and crop rotations that can replenish the soil better, might grow to be better solutions in the long-run.