Wouldn't both of those scenarios be better outcomes than a meat eater that doesn't care about reducing their carbon contributions at all? The vegan with a long commute is better than a meat eater with a long commute, ecologically. And if a meat eater can reduce their carbon in other ways, then that's certainly a better situation than if they didn't reduce it at all.
Personally, I still eat meat, but I try to reduce my beef consumption the most, since that's the biggest emitter.
