Nascar schedules the races, not the weather.
Not everyone's options allow but in the days when my family and I attended races, we always padded days on the back end of race weekends. Never missed a rescheduled race.
Sure, not everyone has the kind of schedule to allow for that but that's on them, not Nascar. Not everyone can be accommodated under every circumstance. While it sucks for those that will be unable to stay, it's a risk you take when attending a sport entirely dependant on the weather. You gotta deal with it or find a new sport.