That's an interesting thought, but do you have evidence supporting this?
Another interesting tidbit about society favoring families with children is the tax implication. In particular, you can claim kids as dependents (which, of course, they are), but claiming dependents gets you tax breaks (and other tax credits).
I'm not saying that's wrong :)
It would be interesting to look at all the tax credits and build the profile for the "optimal" family from a (US) society perspective (as expressed in tax advantages). Then compare that to other countries. This could make a sweet info graphic...