It's been discussed (and dismissed) several times. It's really unlikely that someone would voluntarily walk off or get in a car with strangers while possessing no money, no credit cards, no clothing, no phone. This is not how people usually plan voluntary relocation/no contact situations. While it is desolate, Kelbaker is also a fairly well-traveled road (compared to, say, Hidden Hills Rd). Are you suggesting she voluntarily wandered off into the desert in an act of self-harm?