If that is based on IP logging, in the same way as a forum I run does, then the figures can be very misleading.
Search on Google from flood plains to hunting and you will likely get a hit referring to an NSC page - opening the link records a unique hit but doesn't indicate any interest in...
Less than 6,000 active members - subtract those who don't go to games for whatever reason which suggests that it's not that surprising that many fans haven't ever been on here or even heard of NSC.