Being aware of surroundings and communicating are two different things. You must have either read practically nothing about Terri Schindler and this case, or you have personally tested her and determined through much testing that she has no awareness (thus contradicting many other physicians, relatives and so on).
Even people in comas have come out of them and said that they heard what was going on while in an apparently unconscious state. What makes you so all-knowing that you can say with assurance that Terri has no awareness?
Sometimes this boils down to the fact that some people see the purpose of life solely as the untrammeled ability to enjoy the senses, work and make money, be a solid citizen and so on. While these are worthy acts, the lack of ability to do these does not abrogate one's right to breathe air. Other people see the purpose of life as something deeper, that can be fulfilled or served even while lying in bed unable to care for oneself.
B-I-N-G-O.
If life is simply the sum of the actions an individual can undertake, and the value of one the value of the other, we are all in danger of the next fad of "usefulness" to come down the road. It's a kind of social suicidal depression. It's of the Devil.