@BackFromTheDud but do you actually want kids? I don't have any either, but I can't really count it as a virtue, since it's a bonus not a sacrifice. Likewise not having a car isn't really a loss.
When it comes down to it, I do things when I really want to, and feel guilty about it: flying, eating beef & fish etc. But playing holier than thou isn't all that productive I think, people do what they can and trying to make people feel guilty about their life choices is counter productive imo.