There are lots of reasons. I live in a very liberal área and have very liberal friends. Here is the bulk of it.
First off these folks have a hang up on sex. Even more than the Catholic Church
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if you can believe it. They think premarital sex or ANY form of sex is a beautiful thing and how dare anyone suggest otherwise.
The problem is, like any sin this leads to problems. Unwanted children that are concieved, diseases, and the need to help “take care” of these things.
Planned parenthood will hook you up with anything you need for a wonderful sex adventure at the tax payers dime, and NOBODY will be any the wiser. Not the parents, not the father of the child who is currently being housed by the mom or anything of the sort. The government subsidizes these things because it saves THEM money and they win votes by a public who has rejected any morality related to a Religion (like no pre marital sex).
Basically the issue isn’t about sex, it’s not about health care, it’s not about anything of the sort really. Those die hard planned parenthood supporters care about 1 thing…Rejecting God. It’s hard to believe, but that is the basis of it. Planned parenthood is an outlet of sorts. It’s not them they are supporting…it’s the worship of themselves and the tools necessary to do it at any costs (even a life)