It’s funny: as an Australian that has visited the USA a couple of times (and never been to Europe), I’d repeat half of your points but for America rather than Australia. Some Australians certainly have large vehicles without good cause, but that number is nowhere near as big as in America. (Notwithstanding this, my Dad and I have discussed the concept of a ban or extreme tax on owning big vehicles unless you can justify why you need them (e.g. tradie or large family), with country dwellers immediately exempt for convenience.) And fuel is way cheaper in the USA than in Australia.

You need to go to Europe to see the little cars then.

Australia has half price petrol to Europe and you see this in both car size and engine size.

Also I have read (newspaper so who knows) that Australia allows far more fuel inefficient cars than Europe.

https://www.abc.net.au/news/2019-10-11/australians-car-not-a...

But equally we have a lower percentage of diesel cars which is great for not dying

https://www.sciencedaily.com/releases/2017/09/170918093337.h...

I don't see why a large family would be an excuse. You need a large vehicle because you chose to need a large vehicle?

A large family creates many future taxpayers. The state has an interest in subsidizing or at least not discouraging the creation of large families

That seems like an oversimplification. Rural states receive more in benefits than they pay in federal tax. Large families by necessity are going to favor rural areas and states. It is not clear to me how a large family is a net tax benefit, there are too many other factors to consider.

Having more people pay tax does not mean there is a net increase in tax collected.

> It is not clear to me how a large family is a net tax benefit

Some of the children from a large rural families will move to cities and make careers that pay lots of taxes. Cities almost always have lower birthrates than countryside.

Yes, we need children. That's not a question. The question is if a single couple needs to produce so many children they drive a vehicle so massive is earns tax breaks.

In this context, I assume a "large family" is 3 or 4 children (a 5 seat sedan cannot physically, legally fit 4 children and two parents, and due to the size of modern carseats it can be dicey or impossible to fit 3 of them in compact or midsize sedans even for a 3-child family).

Even just maintaining replacement rate fertility requires an average of 2.1 children TFR, which means some families would need to have 3 or 4 children to get there since other families will have only 2 or 1 child.

In France, you end up paying a lower tax on your vehicle the more children you have, so a family with four children might pay the same taxes on a large diesel as a childless couple with a tiny gas car. I was trying to register my 3-cylinder 1.0 liter vehicle, just to find out I’d have to pay 1500 Euro tax for my gas guzzler. Ugh.

Most things I need, I need because I chose to need them.

> towing your boat/jet ski etc.

A 180-200 BHP sedan can tow a trailer quite easily. You don't need a big SUV for that.

Spotted the "Victoria on the move" plates struggling to accelerate uphill in Queensland on a single lane road delaying the locals trip by an hour to get milk.

horsepower is rarely the limiting factor for a sedan's towing capacity. a sedan's chassis is only designed to withstand accelerating and stopping its own weight (plus a margin for safety and internal cargo of a reasonable mass). you could probably get away with towing a jetski with a typical sedan, but anything much heavier than that risks bending the chassis. even if a car can tow something without deforming itself, the change in weight distribution can make for a very unsafe situation.

I've seen SOOOO many sedans and station wagons pulling trailers here in Europe. The Dutch are especially fond of camping with their trailers and I rarely see any of them using SUVs or anything bigger.

What you're saying is likely not true.

Absolutely. My ex used to drive on the autobahn using an A3 to tow almost 750kg of horse float and horse. The trailer has its own brakes. As long as you don’t drive car and trailer straight off a curb it’s not bending anything.

Here in Australia and New Zealand we regularly tow boats with Aussie sedans like a Ford Falcon or Holden Commodore e.g. https://commons.wikimedia.org/wiki/File:Ford_Falcon_XR8_Ute_...