You mean the magstripe on your license still carries information? Give that man a magnet.
There's an even simpler alternative: Sure, CA licenses may have this mag strip, but the format is not universal throughout the world, or even the US. Carry your passport, which doesn't have a mag strip (last time I checked). Carry a foreign drivers license. Do you know how easy it is to get a drvers license in some foreign countries? They should be valid ID for a bar in California. Next time I'm in some unknown little third world country I will make a point of picking up an official government-issued id. "Yes, Mr. Bouncer, this is my government-issued photo ID. Yes, Tajikistan is very cold this time of year." As for legality of it, it may be legal but it's a sleazy thing to do. I'm sure we are going to see more of this. Larry Ellison may not get his exact dream to come true, but there will certainly be real-time ID verification databases with good net connections, so the teller at the bank will be able to swipe your ID and see your photo come up on his screen. This makes forging an ID essentially impossible, unless you can also hack into the DB in some way.
Do different states use different formats for the data on the magstrip?
Do all states even have magstrips?