I sort of get you, personally I feel the same. But then I walk around here and see people with dogs in baby carriages. Why ? Because they could never have a child, they're too old, or cannot or don't want to spend the money they think it'll require.
The problem does not tend to be that it's physically impossible to get a child.
(Except for Japanese of course. Excluding them from this question)
Seriously, fertility will become no issue if we prolong fertile period of our lives. Imagine having one kid at thirty, and another one at sixty.