Roof rack: Skis. (And the Model X ski box behind car on tow bar solution look unwieldy and ridiculous, but there are still lots of them around here, as the only EV compromise that sort of ticks all the boxes.)
And kayaks too.
Tow bar: Not sure what others do without them. Furniture shops lend out trailers for free so that you can take your new sofa with you back home. I recently transported the materials for building my new front deck on a trailer. I tend to rent a trailer for taking things to the landfill/recycling facilities especially when renovating my home (and Norwegians do a lot of home renovation..). When helping young people move a trailer is all it takes. Etc etc. I used a tow bar at least five times a year for misc errands. (Now I have a Model S and have to leech on neighbors)
I am not sure why this is different and how e.g. US or German or French culture would be digferent.. I guess the alternative is paying others for delivery/disposal, doing less handiwork oneself, and (in the case of US) buying pickup trucks that in no way will fit on Norwegian roads and parking lots.
Trailers are pretty much unheard of in the US. You either have or borrow a pickup truck instead, because everyone has one or knows someone that has one.
As a result, almost no cars in the US has a tow bar. Except pickup trucks. That don't really need them. Because you haul stuff directly in the truck.
The reason most US cars lack hitch receivers is liability. In most of Europe, it is expected you drive slower when towing a trailer. Not so in the US. Even the same models have different tow ratings (usually zero in the US) - see VW Sportwagon for example (rated to 3500lbs in most of EU, and not rated at all in US, despite being the exact same car).
You either have or borrow a pickup truck instead, because everyone has one or knows someone that has one.
In the OP's scenario, furniture, there are very few furniture stores in the United States that don't deliver. And if you happen to shop at one of those few, there are a number of ways to rent a truck for a day or by the hour: Home Depot, ZipCar, Enterprise, U-Haul, etc...
Unheard of ... unless you live in the midwest. Here in Minnesota, a ton of cars have them because a ton of people own boats and/or rv's and/or snow machines. The same reason a lot own all-wheel drive vehicles.
