lots of thru hikers last year who flip-flopped did it from walker pass 40 trail miles south of kennedy meadows. there is a highway there where you can hitch past onyx all the way into bakersfield where i am pretty sure there is an airport. hitching out of kennedy meadows to a bigger town is probably a lot trickier.
Smack
Skywest (United) has four flights to LAX each day from Inyokern. Probably easier to hitch to Inyokern from Kennedy Meadows than hitching to Bakersfield. The large number of government folks from China Lake who travel each week makes the flights profitable. Pricey, but convenient. And for those willing to test their stomachs, the flight east of the Sierra crest between Inyokern and Mojave is always a bumpy ride. But hey, you need a certain amount of turbulence to ensure the pilots are awake.
booger