What makes you vegitarian?

This post is the result of a discussion with two of my collegues.

Days of Salarpuria Soft Zone (SSZ). We used to go for a walk on the big terrace of Wing A of SSZ. Either we used to walk there or go down, walk till Bellandur.

We were walking one day on the terrace. Myself and Das, when even Bikas joined. Three of us were just discussing about something. Always the discussion starts from some small topic, may be a rubbish one.

Things rolled out to carbohydrates and proteins and from that to vegitarian and non vegitarian. One doesn't need a topic to start and stick on to it. It rolls on to something totally unrelated to the started topic and ends up in totally a different one.

Both of them were Non Vegitarians, NV for short. Discussion got heated up. Though I dont recollect the whole conversation, here are a few excerpts. One might find this discussion too immature or too irrelevant. Please put in your thoughts on it if possible.

B : What may be the reason for the brahmanas to not eat non-veg?
S : Tell me why they should?
B : To taste it. Its good to eat it.
S : Is it good to eat non veg by killing them?
D : Come on! don't give me that reason. The so called vegitarians are no better in killing. They kill plants.
S : (After thinking a while) Hey! You can't call it killing. They do not respond. They are relatively dumb. Its better to eat vegitables than killing an animal and eating it.
B : Killing is killing! Right??
S : Come on! Find the difference. Plants do not respond when you kill them.
B : How do animals respond?
S : They cry. Blood gushes outa their body.
D : FYI, plants do have their own kinda liquid for their growth. They do respond in all ways. Only thing is that they are immovable. Only difference between animals and plants is that animals can move but plants can't.
B : Plants do have life right? Don't you agree?
S : Yes I do. We Indians worship plants. We cut plants only for food only when it is necessary. We grow more plants than you breed animals for eating purposes. The degree of selfishness is less when compared among them.
D : Lemme give you another example for the response plants give. Play some heavy metal song continuously near the plant. It will die within a day or two. Play some Indian Classical music, You'll find it growing in a faster pace in a month or two.
S : All those facts I do agree. What I strongly oppose is the cruelity in killing an animal.
B : Killing a plant in that sense is more cruel. You are killing a helpless creature where as we are killing something which can help itself by running. There are chances where it can escape.
S : Somehow I don't buy the idea that killing plant is a crime. There should be a valid scientific reason behind preferring to have plants than animals.
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Went on and on and on...........

Meanwhile there are few theories which Ankur has pointed out in one of my posts' comments wherein people used to have meat (Beef) even in India. There might be proofs to it but I haven't verified it yet. Though there are also rumors that Hinduism bought the idea of vegitarianism from the Jainism. Dunno how true it is or how credible it is? ( Might be a story wound by jains to have an upper hand over Hinduism). There are some jains who don't even have vegitables like carrot, onions, potatoes( Those are roots ) so that it is eaten by earth (Enjalu in Kannada)

Just a few weeks back, an idea struck my mind which would have been the probable reason???!! Plants do not excrete something which is rejected by humans. They breathe out oxygen at day times and apart from that, I don't see anything rejected by plants. ( Don't tell me leaves n fruits).
When compared, animals do excrete. This might also be one of the major reason behind not having meat.

Regarding the killing of animals and plants, it is only a century before that we(Indians only) scientifically proved that Plants do have life in them. Though the ancient people would have known this, they used to worship plants( We get lots of evidence in puranas where people used to worship trees and plants). Even if we don't consider that ancients wouldn't have known this, we considered that plants do not have life and having them is no cruelity. (This point is just for justification purposes)

Do pour in your valuable comments on this topic while i find some other better topic soon.