For me it was two-fold:
1. Ethical: I have absolutely no faith in the belief that veganism is somehow a natural state of being for humans, and I have ethical concerns other than animal abuse that I don't take to such extremes, like my wariness of market capitalism (which hasn't turned me into an ascetic yet.) I think it's good enough to try and get natural animal products from local farms with humane treatment. Death is a part of the cycle of life, so the argument that "meat is murder" never resonated with me.
2. Health: I wanted to commit to a whole foods diet but had no desire to become a slave to my kitchen, or a flavor-martyr.Vegan cooking requires too many substitutions and processed foods to mimic even the simplest of normal cuisine pleasures, and there's very few recipes that are wholesome, quick and easy that don't quickly get boring, or require fancy expensive ingredients.
The thing they share is that I just have ZERO desire to be such a slave to food-needs.
Once I started being able to eat healthful foods without tons of prep or exotic ingredients, I gained tons of energy, lost 20lbs and cut my food bill by 10-20%, even with adding natural, pricier meats back into the shopping cart, and I'm pretty sure I save hours a week being able to eat simpler foods that meet my nutritional needs easily, with no need to calculate how many flax seeds approximate a salmon portion's omega content.
I still eat several vegan and vegetarian meals a week, and often go days without meat products.
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