There are many reasons to choose to live child-free. Some very valid reasons are overpopulation, living with a smaller footprint on the planet, and not wanting to raise fodder for the war machine. Choose from these t-shirts and get the word out.
Enjoy your commute in peace and quiet, eat your meal undisturbed, and shop without rug rats throwing themselves at you. If they get too close just point to your shirt with a skull and crossbones and the words "Child-Free Zone."