It's the only form of motorsport that it is acceptable to watch purely for the pile ups, and fuck me those boys are experts at it.
Having played Nazzer sims, two of which where built on the GP Legends game engine, so I know their physics model is excellent, I would say that there's no wonder they pile up with such ease. I would, if asked to describe the vehicle I had just driven, with no foreknowledge that it was a nascar, say the following.
Some kind of spaceframe, fitted with two pram wheels which only appear to turn left at the front, two shopping trolley wheels made from polished teflon at the back. The machine appears to be propelled by rocket thrust applied somewhere around the rear. Braking is improved several hundred precent by putting one's arm out the window with one's palm facing the direction of travel.
Gotta love the wee flap that flips up to spin them the right way round, only ever seen it on those cars, and it's a genuine bit of genius.
Jefari......Was I tripping or did I see an ad banner appear over a particularly excellent rolling wreck, with a voice over saying "It's the Busch series big one, brought to you by......"??????????

The F1 equivalent would doubtless be.....
"Toyota, sponsors of Ralf Schumacher's latest demonstration that talent is not genetic" 