NASCAR is more a sport for the pit crew, but the drivers do need to have a fair amount of skill too. I was actually involved in a circle track team for a while and while I admit that watching the race is downright boring, the amount of setup that goes into each car and being able to drive that setup to its maximum potential requires just as much skill as any other motor sport. Besides, many of the NASCAR drivers participate in other motorsports, so there really isn't a lack of talent behind the wheel. It's just that NASCAR is a simple form of racing that people who know nothing about racing can enjoy. It's loud, it's colorful, there is plenty of speed, the tracks are small enough that you can see the whole race from your seat, and there is the occasional crash. Compare that to say the WTCC or STCC where your seat may only have a single straight or between 1-3 turns in view and the racing is very technical, and you can see why people who really don't go that in depth into racing wouldn't be all that drawn in.