I can't believe that about taxis in Victoria! What a joke! Why should they be exempt from the law? I think I will write to some pollies about that one.
I do remember giving someone a bollocking at Sydney airport one time as they loaded their <3 mth old onto a lap in the front seat of a car. There's just no excuse to get away with that when you can hire them so cheaply. My mum in NSW will definitely be hiring or borrowing one for when I visit, and the in-laws in Melbourne have my old reversible one. I have a friend who took hers on the plane with her, and I think that's a bit silly.

Anyway, thanks everyone for your help. I'm trying very hard not to think of the cost per use - it could very well end up being $30-40 if we keep going like we are now! Eeek!