Yes they do apply. The law applies to all audio recordings. Grocery store cameras do not contain audio. They have nothing to do with this.
http://codes.findlaw.com/ca/penal-code/pen-sect-632.html
This law applies to "confidential communications".
It is totally reasonable, and almost any attorney could make an argument, that when you are in someone else's vehicle such as a taxi that is operating as a business, in public, that the communications aren't "confidential".
632(c) states:
(c) The term confidential communication includes any communication carried on in circumstances as may reasonably indicate that any party to the communication desires it to be confined to the parties thereto,
but excludes a communication made in a public gathering or in any legislative, judicial, executive or administrative proceeding open to the public, or
in any other circumstance in which the parties to the communication may reasonably expect that the communication may be overheard or recorded.
I don't think there is anything that specifically allows for a drunk moron telling a taxi driver to go to a public location to be considered inherently "confidential". If the drunk moron had been talking about how much of a moron he is on a daily basis at work, to his family, or in his own home, then I think this statute would clearly apply.
Telling a taxi driver, in public, that you want to be dropped off at another public location doesn't scream "confidential communication" to me. I mean, if the Uber driver's windows are rolled down, it is reasonable that drunk moron telling the driver where to go would be overheard, because, you know, they're in public and stuff. Boom, not a confidential communication...because of a rolled down window. And that leaves out the whole "reasonably expect that the communication may be...recorded" aspect.
Since California is a common law jurisdiction, there are case law opinions that can clarify this, and an attorney can always find out what is common practice, i.e. if taxi services typically record business transactions such as taxi rides. If there are taxis in California that record, or really any type of business that records transactions in public, then it isn't inherently reasonable to believe that the communication would be considered confidential.
I doubt there is going to be a summary judgement against the defendant simply because there is a recording of a drunk moron committing assault and battery...at least if the defendant has an attorney.
Uber should definitely hire a team of attorneys in this case. Prove that you'll defend your subcontractors and you gain awesome credibility as a contractor/company, and, hell, bring about a little justice at the same time.
If Uber lets this guy hang out to dry against a drunk moron with an attorney, then you better second-guess becoming a subcontractor for Uber, no?