A few thoughts (I don't work at Google, but a similar large tech company in the south bay):
1) Yes, $2000 a month is expensive for corporate housing. But if your goal really is to save money, you can find a room in San Francisco for under $1000 in a co-op or such and just take the shuttle to Google every day. It won't be the most beautiful house in the world, but it'll beat a truck.
2) If you like bringing home cute girls/boys, that's going to make things significantly harder.
3) I have a fair amount of expensive equipment (photography + music gear) that I would not be comfortable leaving in a vehicle for extended periods of time. It'd just takes once to lose a pretty significant chunk of cash (probably something like $5k in photography gear and close to $10k in music gear, for me).
4) Even if his name and face were withheld, anyone working at Google will remember that truck very distinctly now. Not the smartest move for him, he's probably going to be found out in the next week or two.
I have friends who did similar things - whether to save money, or to entertain a more minimalistic lifestyle. I'm still very curious about it, mostly for the latter reason, and would love to read any detailed experiences if anyone here has done it.
Here's one link for a few years back: http://austenallred.com/voluntarily-homeless-in-silicon-vall...