I agree with you that there are a substantial number of people of childbearing years who chose to have no children. This concerns me greatly because the current pay-as-you-go system of Social Security makes my children the payors and guarantors of the benefits that must be paid to these same people when they retire.
My wife and I have willingly given of our time, love and money to raise our children. These are our gifts - our endowment - to them that we give to them freely and with no expectation of economic return. But instead of these gifts and endowments being used for the benefit of our children, the current Social Security system will take these away in the form of higher taxes and give them to all cohorts of my generation - parents and childless persons alike.
So in the future when I come to be elderly, parents who have invested their time, love and money in children, will see their endowment shared with childless persons who instead invested their assets in better lifestyles and stocks and bonds.
This is why I say that Social Security is anti-family and anti-parenting.