If you're really being serious, then the answer is that most (or, at least, the vocal majority) of those people don't even really care about living children. I don't see that type of person generally giving any more care to a non-human being than they would a human being, and they already don't care about people other than themselves.
"Pro-life" has always been a misnomer. More honest descriptions would be "anti-choice" or "pro-forced birth."
The real true reason most people are against abortion isn't because they don't believe it's a necessity. It's because they are afraid that some woman won't be punished for having sex. Whether or not the fetus survives isn't the point, it's that someone has to be punished for enjoying life.
Yeah, in my defense, my head hurts like shit and I can barely think.
Christians are usually the ones against abortions, and it seemed to me the people the original comment was talking about were conservative christians, but I see how my comment is not entirely relevant.