Actually, you will still find stuff like this on the 'Ring.  However, there is less overturning since today's cars are much more stable.  But the junk-filled and people-filled cars, and drivers without helmets, you'll still find.  The reason is that the 'Ring is considered a toll road without a speed limit as far as legality goes.  You're responsible for your own safety and any damage you do while driving on it.  If you want to drive around in a shit-filled econobox with no helmet or seatbelt, you can.  On most days, you can literally just drive up in whatever you're in, pay a fee, and go drive around the 'Ring.  Just don't go crying to the track owners if you get flung off the Carosel and get maimed.