I have heard people occasionally wonder whether their participation in the track event would be reported to their insurance company. Under normal circumstances, it won't (and never has been, at eight previous NSXPOs).
The only circumstances in which I could foresee this information being used is if there is an unresolved liability issue. For example, let's say you drive off the track and damage a guard rail, and it costs the track $500 to fix it. We (the club) would contact you to arrange reimbursement for that expense. If we were unable to arrange this, only then would we consider contacting your insurance company (and only as a last resort, after trying to work things out directly with you).