Just because one can have a child, doesn't mean one should.
Just a few thoughts:
1. Children are little human beings who need to be loved and nurtured.
2. If your child is terrified of you, you shouldn't be a parent.
3. You are no hero if you adopt a child from an orphanage in a poor country, or from the crappy US foster care system, and then treat them like dirt in your own home.
4. Children are not accessories to be used when convenient.
Many of us, gay and straight, stand by quietly as we witness some parents killing the spirit of beautiful children. We rationalize that people have the right to parent with their own style of discipline, their own values. Who are we to question someone else's parenting style?
To a child, we could be their savior.
Whether we know these abusive parents or not, whether it is in the grocery store or at the local restaurant, if we don't stand up for these children, then are we any better?