Hmmm You're right. It doesn't make a good argument unless they agree to listen to it be fully explained...
When our society produces the qualitative outputs as it does (increased mental disorders, increases health disorders, increase in working hours, decrease in environmental health, etc) it makes a fairly easy case against the continuation and support of said society. I don't believe there is a single quality of life metric our society at large produces that is favourable against a simple alternative society (that would be entirely in favour of families spending as much time together as they'd like, this would include our natural inclination to teach and be with our own children) the simple idea of having both parents spend the majority of their waking hours not with their children and not together; but at 'work', in my mind is patently absurd. Any system that produces these situations is not creating much "benefit". So, I believe that not supporting such a system would actually be in everyone's best interest.
Raising my children to be capable of living-in and creating a new society is, in my mind (and heart), the only argument I would ever need to support my decision to raise my own children.