Regarding the "children have potential" argument - what about the kids with little chance of significant contribution, like those born with severe mental disabilities?
This should be about children's rights, not expected futures. Children have enough to deal with without feeling indebted to society for existing.
You are not the only one that cares for them. What about them? Those who want to care for them, should do so. It's very simple.
If you want something, it doesn't mean you are entitled to steal and enslave to get it.