Have you heard of the WATER FOOTPRINT?How vegetarianism can help in dealing with foodshortage

A lot of people have started using the word CARBON FOOTPRINT more and more in their conversations, just like , using the word , 'Going Green', or the word, ORGANIC, has become another fad.
The part of this whole repeated misuse or overuse of the word without actually ever really understanding the concept of it or without actually truly doing something about it, is what irritates me very much and each time some ill informed person just goes yada yada yada about green or organic or most recently carbon footprint, All i want to do is make them sit down and then proceed to ask them to explain the concept to me.
Anyways, let us come back to CARBON FOOTPRINT.This is a broad indicater of how much of the non renewable resources have each one of us as single entity used up .The larger the footprint , the larger the wastage that has been done by us.
Now, A waterfootprint is much the same, the amount of water that one wastes and the amount that one doesnt need to waste or the water that they could have prevented from getting wasted had they been careful .
For eg. you know we spend so much of water feeding a cow,, approximately 40L of water, just so that we could drink a Litre of milk.So, we have had to invest 40L of good to drink water for just a mere 1L of milk
I mean, really, it is absolutely wastage.Soymilk prepared from beans uses water to grow the plants but ofcourse that is all it needs besides soil minerals.
One pound of soybeans , Yield a lot of soymilk besides the byproducts thereof after the milk has been extracted which are absolutely edible and rich in minerals.
We could very well, skip the step of feeding the cow the soybeans and then drinking the meagre yield of cow's milk
The cow needs to be fed as well, besides being given water, to produce a Litre of cow's milk.
Get my point?
we could have saved that much of food and that much of water, had we decided to just go ahead and drink soymilk .While excluding a step in the foodchain we save a lot of resources.
We feed the cow, corn and soybeans ,peanuts and what not, which for a fact , could actually be useful as food to us ourselves.Thus, by eating that very corn and by eating soybeans and peanuts and not breeding more cows just to be slaugthered, we are actually countering the food shortage.A 40L of water would be enough for twenty people for a day.The amount of feed that a cow feeds per day would be enough as filling meals for five or six people.
Simply said, if we can eat wheat and carrots and soybeans and corn ourselves, why go ahead and feed pounds and pounds of that to a cow and finally kill the cow after having fed the cow for months this way?
Had we been a tiger or a lion or an alligator which cannot survive on carrots or soybeans , i would never have suggested this idea.
Afterall, our ancestoral primates were herbivores.We sure can go back to that and save the environment.

Do you know of the water foot print?