Where all food is abundant, it is easy to take some silly moral stance against some food over others.
That may be, but India has the oldest tradition of vegetarianism, (I think), and food has not always been abundant there. Still isn't in a lot of places. Was it a moral stance or a pragmatic one to avoid eating animals there?
I never thought about it till just now. A hot, very hot, tropical region with a rainy season. Could a meat eating culture even exist in that situation? A huge population, but limited land, but lots of water and sunshine.
If they ate meat, how would they keep it fresh? How could the culture afford the land and resources to even have enough animals to eat? The choice of that culture, which worships the cow, is possibly a pragmatic one. By feeding the cow grasses and some grain, and using the milk fresh, or fermenting it (whey, cheese, butter, yogurt), they avoid spoilage of animal protein, get immediate high protein/high fat food, and have animals for labor as well.
Now the issue of including milk as vegetarian food arises. India was an example because it is an ancient Vegie culture, with limited food sources.
I don't think you could even have a vast meat eating culture in that climate. With slaughter comes disease, scarcity, and less food from the same amount of land. Utilizing the living cow for labor, as well as a daily source of food, is possibly better economics.
Fruits, nuts, seeds, legumes and grains grow well in a tropical climate. Especially rice. Combining those sources with animal protein/fat from milk was obviously a workable solution to the area. I can't see how the culture could have survived otherwise.
Some African herders also do the same, not killing the animals but eating the blood and milk daily, increasing the number of animals, rather than killing them. Killing a cow is a rare event. Too valuable alive. I don't know enough to say for sure, just musing aloud.
It is an interesting subject. There are all kinds of health risks from eating meat that are avoided by vegetarians.
And in regards to the ever present questions, there was a huge study done on this. (forgive me if it has been mentioned, I didn't read everything yet). The evidence was overwhelming. Vegie health nuts really do live longer and have less illness. The main factor seemed to be fresh fruit. Five servings a day of fresh fruit cut the risk of all deaths in half.