Save the environment - don't breed!

I'm getting a little tired of people whingeing about saving the planet while not curtailing their breeding instincts. The planet's problems are largely due to overpopulation, imnsho, and so it's only logical that the single biggest contribution any human can make to preserving the environment is to not have any children. It's that simple.

Baby On Board

For the life of me I don't see the point of those stickers on cars proclaiming "Baby On Board" and the like. What are these people trying to tell me? Are they saying that I need to be careful not to get too close to their cars - something I tend not to do in traffic anyway? Or are they warning me that they may be distracted by their offspring while driving and may become a little erratic ... in which case, what the hell are they doing on the road in the first place?!