I have a question for you. If you were ordered to pay a million dollars a month in child support could you? For some men $500 a month might as well be a million. They can't do it. They don't have the skills, the education, the work ethic etc.etc.
Instead they get cought in a cycle of falure that they can never escape. I agree that men should not have children if they are not prepared to support them but many do any way. If you corner a man and give him no hope of ever putting his head above water you can expect some less than desirable outcomes.
Its unfortunate but without hope human nature can create highly unstable people. It would actually be a kindness to lock them up and throw away the key.