It is surprising that Nascar can be called boring. It has one of the largest turnouts of any sports. TV races have huge followings and ratings. I never find it boring. I do like other forms of racing too of course. Even Airplane Pylon Racing requires going around a closed course with turns in one direction, but it is anything by boring. :S
Last I heard,Formula One is the most attended and watched sport around the globe, followed by soccer. NASCAR is distinctly American and doesnt doesnt have the global following that other sports do. I also saw stats once that showed Ice Skating brings in the most TV viewers in the US. So, go figure
NASCAR fans are a little more sophisticated, intelligent, and genteel than soccer fans. After all, one never hears of NASCAR hooligans or NASCAR riots. In addition, NASCAR fans don't stand on the race track as they tend to do in rally racing. Finally, even Jeff Gordon's rainbow car is tolerated!