There was actually a time when I ate vegetarian for a while! Like a few years or something? But I think when I don't eat some kind of meat or fish, it's quite difficult for me to be full, even eating other proteins like tofu or drinking soymilk. That's why I still eat mostly chicken and fish. I don't eat as much red meat (but if I have a lack of options or want to eat something specific then I still do so, just it happens only occasionally). I eat less meat and fish when I can cook for myself, though, and more when I have to eat out since there are less options. When I'm active, I get hungry quite easily, so I even have to eat extra food (but I eat more like two meals a day).
I agree with a lot of people raising the point of how it's awful how most commercially bred animals are treated before killed for their meat. It would be great if there were more ethical standards for how they were treated and also if, like other people mentioned about indigenous peoples using all parts of the animal, every part was used and none left to waste.
That's why I generally follow a policy of as little waste as possible. Whatever I can eat, whether I cooked or bought it, goes in my stomach, unless eating it will make me sick for one reason or another. Or if it really tastes THAT bad. When I see food, I don't just think of it as something that goes in my stomach. I think of all the effort it took to get to my hands and my table, the nutrients that fed the crops from the earth, all the people who grew and harvested crops, the people who transported and sold them, sometimes also the people who cooked them, and what a waste it would be to discard such perfectly fine food. In the modern world, your ingredients may have traveled across the country or even the ocean as well to get to your local store or restaurant. Plus, there are plenty of people who are not as privileged as I am to be able to eat or even choose what to eat. Of course, not everyone has the privilege of having the health to do the same, but since I do, I try to finish what's on my plate as much as possible.
I try to live in accordance to my values to the extent I think I am able to, although in this modern world, I often find myself compromising them, which makes me quite sad. I would like it if they made more lab-grown meat or more cheaper and accessible meat alternatives aside from what we already have. Suffering is not required for the meat and fish I want to eat. I admire the people who are able to and do stay true to their principles and refrain from eating unethically butchered animals.