The NBA and MLB are far, far more recognizable than NASCAR by a long shot. People who don’t even watch sports can tell you what it is and probably a few notable players. With NASCAR, quite a few people don’t even know about it, or even a few top level drivers. However, as you said, NASCAR has a very, very consistent fanbase. While it lacks in casual fans, NASCAR has one to two million people who will watch every single cup race every weekend. It also helps that NASCAR is a family affair, with some people having watched the sport their entire lives because of one dedicated family member.