Vegetarianism was meant for the lower caste members only originally when the aryans invaded and conquered them.
>They forced all the jeets to be Vegetarians while they are the meats, that way they could have a large agricultural base to grow a caste serf population with while eating like the warrior kings and lords they where for the early part of Hinduism
>full vegetarianism for upper caste really only came into play after all the Indians got their freedom from the Moghul empire as a means of hindu nationalism and unity (plus much of the once elite members were killed off; lost to the Arabs because the aryans bred with the jeets and lost their divine right to rule; becoming tiny frail people unable to defend their empire).