I've been to 2 Nascar races, and I'll have to say that while it might look stupid on TV (and some of it does) it does no justice for going to the event itself. The noise, adrenaline, and excitement of being at a race is definitely something you have to go to in order to understand fully.
While it might just 'look like cars going around in a circle for 3 hours', that is just like saying hockey's just some idiots trying to hit a puck around with a stick.
Nascar is the most popular sport in the US behind the NFL and does considerably well even when up against football in ratings. Something hockey could barely hope to do. Not only that, NASCAR is expanding pretty rapidly. It used to be just a redneck sport, for lack of a better term, but if you go to a race now, there are lots of suburban and urban viewers of all races. NASCAR's also expanding to Mexico, and from there who knows.
Hockey could learn a lot from Nascar as far as marketing goes, for one thing, the drivers themselves probably have a lot of similarities to some hockey players, yet the major sponsors Nascar brings in helps market those people to everyone.
You can call it a hillbilly sport as much as you want, but like it or not, that hillbilly sport outclassed hockey pretty fast.
And don't get me wrong, I think Nascar's ok. I like going when my dad's got tickets, and every once in a while I'll watch a race, but I'd rather go to a hockey game in a second. But Nascar has done it's homework where the NHL hasn't even started.