Track days are very risky, I agree with your 1% theory, but that equates to 2 cars for every 3 track days .
I too agree with the "silly" part too, as I have since learnt a very valuable lesson; EASE the power on, when coming out a corner But these lessons are only learnt through experience. Most are lucky and have no damage for their mistakes, but some will pay the full price. Just letting people know the risks involved and making them think wether they are financially secure. In my opinion if the car is under finance or loan, I would highly recommend not to track the car, as these people could not afford to write it off.
You only need to look at the professionals, to realise how risk this sport is.
If you can afford the maintenance and repair cost, I highly recommend taking the sport up. It is a HUGE rush and great fun when everything goes right