In the past and I suspect this time as well you don't have to sign up to hang around many of the events. I would not expect you would be able to attend things like the dinner, the muesum, and track. But the canyon drive or general gatherings in the parking lot or around town (palm springs is small) Would not be a problem people will tell you the schedule and just show up. I did that in Vegas and just did the HPDE track and skipped all the other paid stuff but still hung out. I even stayed in the same hotel.