^^ Totally agree.
But to stay on topic - Dan, I reckon what you're trying to arrange is a great thing, but I reckon the cost and apparent lack of commitment from the required number of members to sign up and pay is going to see this keep getting postponed.
I reckon at this stage, given the following: a)cost, b) lack of member commitment at this stage and c) majority of members not having done a track day at all, it would be a better idea to maybe lunch of another, already organised track meet.
Winton do practice days on Fridays, I know it's a bit of a hike out of town compared to Sandown, but you don't need to rely on having enough members sign up to ensure the day goes ahead, ie those who definitely want to run can turn up and run and the cost is a helluva lot less. Winton is also a better learner track IMO, as it's not as fast as Sandown and there's less armco to hit if you run off or things go pear-shaped (mind you - there are still walls to hit at Winton - trust me..!)
You won't have instructors or the such, but if it's organised enough, perhaps more experienced drivers could be supported to attend and act as instructors. Bare in mind that these days aren't for setting track records or burning the hottest laps in town, the whole purpose is to get used to how your car behaves and feels at speed.