Bad DNA, why do we protect it?

I like playing Devil's Advocate, and this subject is perfect for such a role. Here is the story. Lately many British newspapers have reported about a man named Keith Macdonald who has been labeled 'Britain's Worst Father'. Apparently the man (now 25) already has 9 children by 9 different women and is expecting a 10th by his 10th girlfriend. Mr.Macdonald had his first child at 15 and, crucially, he does not pay any money for child support (He is himself on a £44 a week unemployment benefit, so he is supported by the state). It is expected his children will cost the British taxpayers £1.5 million in benefits and childcare. Meanwhile he has publicly stated that he will never use condoms (which has some people calling for a forced vasectomy).
The question I want to ask about this story has nothing to do with the actions of this man or any action the state may or should take against him. I do not want to discuss any of his former girlfriends (who are clearly welfare-lovers) either. Rather, I want to ask a more fundamental question: Why are this man's children our business? It seems by supporting them we are bailing him and his lovers out. They completely avoided the consequences of their actions!
Now most people would reply: It's for the children! They are innocent in this scenario and we as a society must help them.
To that I answer - why? Indeed they are innocent children, but we did not harm them. It would be nice of us to help them, but we don't have to do it. The children have parents to take care of them. If the parents fail - so be it. May I just remind everyone - these children are the offspring of their parents. They are carrying their obviously inferior genetic material. Now what happens when we support not only psychological inferiority (helping the lazy and the stupid), but also genetic inferiority (helping the children of the lazy and the stupid)? It must also be pointed out we are helping these kids at the expense of others, whose parents were not irresponsible and actually make money. So we are in fact subsidizing fools and their children (who are more than likely to end up fools themselves) by taking away from intelligent people and their children (who will most likely be successful). Is this in any way fair or just? Does this in any way help society progress? It feels good to help, and it feels right to help, but is it right? Deep question - think about it.
Interestingly, it is written in the Bible that "the sins of the parents are visited on the children to the third or fourth generation". This means that if the parents are sinners (do not take care of their responsibilities) then the children will have poorer lives. It is an obvious statement which many people fail to grasp. So, would it be just to alleviate the consequences placed upon people by the Law? The Law of Nature, the Law created by God?