I agree that a beginner or anyone else doesn't need a new set of tires to participate in a track day, but they will surely use up a huge portion of the tire life once you track the car. It won't be long before you will need to buy new tires, specially if it's the rainy season.
The problem with using stock brake pads new or used is that after a few laps the brakes will fade and pretty soon the car just won't stop. Stock brake pads can only take so much heat before loosing its braking ability.
I will disagree however on the 5 point harness versus standard belts/air bags. I think that not only do the 5 point harness belts keep you strapped in without moving around in the seat, but also keep you in the seat in case of a side impact. I don't know of too many instructors that will get in a track car without having the proper harness.
As you said "Just the experience to be able to drive your street car on a race track is a thrill the ever gear head needs to try at least once" is exactly what I am trying to promote. I work very closely with clubs like NASA and bring many school graduates to participate in their lapping events.
We are at most track events throughout the year, and invite and welcome all Corvette owners to stop by. We help anyone with a problem and usually have parts in stock to get them back on track.