Chuck,
As a racer I can tell you the ONLY two things that factor in to where and when I race.

1. DISTANCE. If it costs me over 100 in gas to get to and from a track, I'm not racing. It's a hobby for me, not my life. It already costs enough to do this and I'm not a world of outlaws driver.

2. Weather. This goes hand in hand with the first one. Forecast shows 60% or more...chances are I'm not taking the chance. Again this has to do with cost to get TO and FROM the track. I never blame promoters for canceling based on a forecast. If I ran a track, I'd do the same thing. How many fans end up not going if they think it will rain out? Probably more than you think.