I could ask those same people why they eat meat, but I never do. Maybe I should start answering their question with the same questions they ask me. That will usually shut people up and get them thinking about themselves which takes the focus off of you.
I don't want to take tons of medications when I'm 45, 50, or even 60. I want to be free of all medications no matter if I'm 40 or 100 years old. My goal is to have good health by eating the foods that are best for the body to function.
I don't eat meat because I know it is not healthy. Dead animal flesh is full of toxins no matter how it is prepared (baked, broiled, fried, barbecued, steamed, etc.) and can lead to an early trip to the grave. In the long run, what good will meat do for the body.
Once dead animal flesh gets into the body, then it passes through the digestive track very slowly, rotting away in the body. Toxins from dead animal flesh causes sickness and disease, not to mention that it stinks when left out of the refrigerator for a short period of time.
It only seems right to eat those foods that will give life to the body. If we eat a diet high in animal flesh and animal products on a regular basis, then our health will soon suffer. We are what we eat!