Because it's supposedly a free country? Because driving a powerful car does not necessarily mean you're dangerous (or more dangerous than others on the road)?
It's a psuedo free country, there are plenty of things you can't do, but point taken - if you want a 300kW car to allow you to drive at the speed limits be my guest.
I agree that driving a powerful car doesn't mean you are a dangerous driver, but I never said that did I? I can understand the reason for luxury perhaps, but power? Seeing we're just driving around the city and all.
But then you might also question why a person chooses to buy a massive 4WD just to take their kids back and forth from a suburban school?
Free country there too I guess - or do we assume anything about the abovementioned driver also?