I have had a friend or two refuse gas money from me for the Burn because they "would have been making the trip anyway" (although I have always persuaded them to accept $). So . . . someone likes her enough to let her ride free. That's a good thing. It doesn't take away from the unavoidable lesson she's getting anyway: having extra savings or a contingency plan is wise, whenever you can.
MJ, it's unlikely that total strangers will allow you to ride for free, so you might need to search the couch cushions, but that rideshare link is: http://rideshare.burningman.com
And there's a rideshare desk on the first floor of the Reno airport.
And this is a big obvious thing, so sorry in advance, but---don't take anything illegal into someone's car unless they know.