I don't get why the mini-van get's such a bad rap - it just boggles my mind that people actually see a car as a reflection of their masculinity. Buy the tool that is the best for the job and in many cases, for large families, it is the mini-van. I am old enough to remember when mini-vans first debuted. People thought they were wonderful, until somehow they weren't and people decided that a light truck was appropriate for driving on everyday paved roads. At least now the SUVs are starting to move in the right direction - crossovers have lower profiles, better gas mileage while still offering the same benefits as an SUV. I actually laugh when I see the word "crossover" because they are really just slightly taller station wagons which is what families drove before minivans.
As far as how many kids someone should have....it's hard to say. It is an interesting question because it is not cut and dried. Some parents I wish had more kids - my MIL and FIL should have had 10. They were that good at it. But they only had 2. My parents probably should have had none, but I am sitting here typing on this keyboard so I am glad they made that mistake. ;) Part of my decision to stop at two kids vs. three was financial. I wanted to funnel more resources into the children I had, but I won't fault others for making a different decision.
I don't think using finances to determine the amount of kids someone would produce the best result. I'd almost rather see potential parents go through a process similar to what adoptive parents go through, which does include financial ability to support a child, but also includes mental and physical health requirements. I don't think we are there yet, but I could see this becoming a possibility if overpopulation becomes a problem.
Aso, I disagree that a child is a "luxury". A child (looking at them from a cost benefit standpoint) isn't just a "luxury", it is also a "public good". A child, if it becomes a productive adult, is a net benefit to society because it produces goods and/or services that benefit everyone. A "luxury" is just a gratuitous good that benefits yourself and contributes to your own comfort only. I don't view parenting a just a right, but as a responsibility to produce a happy healthy human being that is a positive good to society. If you feel that bringing a child is purely for your own benefit, then you are doing it for the wrong reasons, and should not have children. In that case, get a pet.