> if you don't pay your taxes, they might not take your house.
At least in the states they absolutely do. It starts off as a tax lien which is then sold to whoever wants to buy it, so that the private sector handles actually reclaiming the land and re-listing it on the stock market.
That is just how US law is structured though. They could just as easily say that they will reclaim the loss through recovery of your assets or by weight in blood.
In the UK the process is different, which just shows that they don't have to take your house to reclaim outstanding taxes.
The point is that the government has options, if the property recovery value doesn't cover the missing taxes then I'm sure they will recover through other avenues. If you lease a car and don't pay, they can really only reclaim the car.