I’m sorry to say the clues are in the OP. Nowhere does it say you can pitch up and drive your own car. However, it does say you can SEE some incredible Supercars so if you put those two together you get what you got. Put it this way, if you had a Zonda and put it on track, would you want every chav with a beaten up Pug trying to barge past you so they can tell their mates? I appreciate you, most probably, didn’t rock up in an old sh!tter but they have to draw the line somewhere, and that line was above you in a Maserati. Sorry.
I hadn't seen this prior to today , as Benny says , it reads as free entry to watch some cars on track for an hour , if I thought different I'd at least have rung and asked before making a 200 mile round trip.