I entirely agree that where you live and with the committments you have you need a car, and also that it's very cool that you can cycle to work, and their attitude is irritating.

However, I want to take issue with the cars are inevitable consequences of kids thing.

Cars are inevitable consequences of suburbs.

I have never driven and am a parent -- but I have made choices about where to live and work that take not having a car into account. And Z goes off on the bus with his sh'nai and his kit quite happily. There is a bus, because I chose to live where there is. I can't cycle or drive or even walk very far, so I need there to be.