What about the childless, and those who never want children?

They pay for everyone else's children through their taxes. Money they could use elsewhere for their own needs or pleasure.

-- To be clear, I'm not saying this is necessarily a bad thing. I don't have population charts of Austria on my desk and I'm too lazy to Google it right now, I'd assume it tracks a similar trend to the rest of the Europe and it's slowing down. In that case it might be for the common good and might come back as a positive to the individual at some point in their life.

I'm just saying it's not easy to come up with a scheme that is/feels fair to everyone involved, especially if there's no justification for it. One could find justifications for child support maybe, but can you justify freeloading just as easily?