When anywhere from 1000-1700 fans are camping the entire event, I don't think Attendance is a problem.
I remember Fishinman stating a burg race about four years ago where he counted less than 200 fans in the stands. I've seen no less than 1500 and ususally closer to 2500 since Rudy took over
I went to a couple LM races within the last few years at Brownstown and never had a problem. Its probably been 20 years since I went to a Jackson Nationals which ended at 6am in sunlight LOL. Even went to a WoO event back in the early 90s that Steve put on. Course I almost always get to a track before 3pm, The people, the atmosphere, Final track prep, hotlaps, Its all part of the event for me.
Chuck