Back when I was eating meat, I was probably still aware that it was harmful, but in a kind of cynical denial about it.
I've heard that one about "the annual crops" before, and it's simply not true that it's "the" alternative. It's claimed in this one study that's echoed in loads of articles[0][1][2][3] that assumes that vegans don't eat perennials, which is kind of ignoring the existence of apples, apricots, asparagus, artichoke, avocados, broccoli, currants, basil, blue- and blackberry, chives, fennel, garlic, ginger, grapes, kale, kiwis, leek, mint, onions, oregano, pears, persimmons, pineapples, plums, pomegranates, potato, rasp- and strawberries, radish, rhubarb, rosemary, sage, thyme, tomatoes for a start.
This view about animal husbandry being harmless for the environment has been disproven[4][5][6], and is on the line with global warming denialism.
[0]: http://qz.com/749443/being-vegan-isnt-as-environmentally-fri...
[1]: http://www.pbs.org/wgbh/nova/next/earth/going-vegan-isnt-act...
[2]: http://www.foxnews.com/health/2016/08/11/new-study-reveals-v...
[3]: https://quietkinetic.wordpress.com/2017/03/09/global-veganis...
[4]: https://www.theguardian.com/environment/2008/sep/07/food.foo...
[5]: http://www.cowspiracy.com/facts/
[6]: https://www.theguardian.com/environment/2014/dec/03/eating-l...