in a true free market, parents would desire that their offspring were as healthy and wholesome as possible so that they could be as competitive as was necessary to succeed and excell in whatever endeavors they might choose
there might be individuals and/or couples who desired to produce "less-than-whole" and/or handicapped and/or retarded offspring but then they might well be burdened with caring for them throughout their entire lifespans...which, after awhile, would probably cause them to kill their own offspring...
enjoy!
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