Don't the largest most polluting machines work on the plant farms?

I'm talking grass fed animals. I agree with you that we shouldn't have grain fed cattle

Animals it's light trucks and tractors up feed the animals during winter or drought, then transport to market, eventually to the consumer.

Plants it's fertilising machines, crop dusting planes, massive harvesting machines then usually through factories eventually to the consumer. If you eat while foods only and nothing manufactured then it's massive harvesting machines then to market to the consumer