Environment is a big part, though. But yeah, there are a lot of other reasons, too.
But having a car that leaks oil is extremely bad for the environment.
Can you list some reasons? Maybe what I'm classifying the some of the benefits as something else.
Health is a big factor, people who eat more meat are apparently more likely to get certain kinds of cancers (colon, for one). Plus, meat has a lot of fat in it, which is healthier to live without. Plus, animals are fed a lot of different chemicals to make them grow more quickly, which isn't something that I really want to be eating.
Moral reasons, which basically boil down to utilitarianism. Do I get enough happiness out of eating an animal to justify its death? I decided that I don't. It doesn't seem right to me for an animal to lose its life just so I can have a meal that I don't even enjoy more than an equivalent meal without the animal.
And then environmental reasons. The meat industry is the biggest contributer to carbon dioxide in the atmosphere (very little of which is removed by plants used for farming, incidentally -- most of it is removed by forests, which are frequently destroyed by the meat industry
).
It's also cool to change eating habits because I get to try a lot of new foods.
Those are the primary reasons. And incidentally, I'm not out to change anybody's mind. I'm only listing them because I was asked to.