Though Hindu Scriptures permit its followers to have non-vegetarian food, many Hindus adopted the vegetarian system because they were influenced by other religions like Jainism.
8. Even plants have life
Certain religions have adopted pure vegetarianism as a dietary law because they are totally against the killing of living creatures. If a person can survive without killing any living creature, I would be the first person to adopt such a way of life. In the past people thought plants were lifeless. Today it is a universal fact that even plants have life. Thus their logic of not killing living creatures is not fulfilled even by being a pure vegetarian.