Let me put it in this way....
Even those who have committed crimes are helped by the yellow ribbon project when they have served their sentence.
One cannot deny a child of a unmarried mother benefits like baby bonus, reduced childcare leave (2 instead of 6) and later say: Wow! look at that, the kid has grown up in a single parent family and look at the problems he/she has!
It's the same as pulling a baby out of the womb and say: Wow! look at that, the life is not viable!
Unmarried mothers are not contributing to the ills of our society, it's the fault of those around who landed them in such a state. Children these days grow up ill bred not because of single and unmarried parents, it's because of lousy parenting skills!