There is no law against the number of children you can have, but I think there should be - it shouldn't come under human rights, it should be a worldwide thing that we need to limit the population and measures need to be taken to help with that.
So if you were in a Casino and someone came up and told you how to cheat at one of the games (not just a system, actually CHEATING) would you take it and get loads of money from it or not? I personally wouldn't and I see this kind of thing as being very similar in terms of morals. We all have the ability to use the system in that way but most of us choose not to, we choose to go to work and earn our living, because we have morals and a desire to help out our society rather than just take from it.