Veganism

Not just ignorant, benighted. Which is to say, it isn't an accident.

Agriculture gave us the ability to easily grow enough plants to feed everyone. But what if you're not growing food to eat, but to sell? You can only use so much food, but you never have too much money! Now a farm is capital, and capitalism demands growth. But we're already feeding everyone! No problem, refine those cheap, safe, plentiful plants using the bodies of animals to produce scarce and expensive (if unhealthy) meat. Now the economy can support many times as many farms!

It's in the interests of the capitalist owners of our culture for us to eat meat. There will always be a strong anti-vegan influence exerted through that culture, keeping us ignorant.