There seems to be some grey area for events. I have heard you don't need a license, but it could have been, for example, if there was a net control running the event. There is also wording I've read about in order for a non-license to operate a station, a licensed operator must be in "attendance," which would leave things a bit vague.
As an operator, I can hand you my radio and you can chat with folks on the other side. I am responsible for making sure the rules are followed and the call sign is transmitted as required every 10 minutes and at the end of the transmission.
There is no gray area about an unlicensed user using their own radio from their own truck on HAM frequencies. GMRS, however, is a giant gray area, even light gray.
Get ur maps! Fullsize, high-res versions below. Best if printed on 11x17 paper, in color, from your work's printer
The entire Tahoe/Plumas National Forest (THIS ONE IS HUGE, YOU HAVE BEEN WARNED!)
I am bringing with me a GIANT sample print of the full version suitable for hanging up in the man cave. It's waterproof, on vinyl-coated canvas and about 36" square, maybe bigger. I'll have contact info for a print shop (that I do some IT work for) where you can order one for $45. He could do it even bigger if you want.

, with possible light shows off and on.