Once more, this is a matter of apples and oranges. Some men do place a low value on certain children (Moslems don't think much of Jewish children, for instance). This is a value judgment, which is precisely about which we were speaking.
However, simply because one places a low value on a specific person does not mean he can do whatever he pleases with that person -- especially if he expects to live in a social grouping. "Morals," when one comes right down to it, are simply ground rules which members of groups have agreed upon to limit conflict within the group and hence promote survival of the group. And, typically within a group the members place very high value upon one another. However, when dealing with other groups our perception of their members' values is more variable. Hence you get racists, and whatnot, which supports the view that human value is purely arbitrary. And this is all we are discussing -- whether human worth is subjective and arbitrary (which the evidence supports) or objective and absolute, for which there is no evidence.