Remember that the bouncers and waitresses are minimum wage people who could lose their job if they let someone in with fake ID. Not being travelers, the only "travel" ID they are likely to be familiar with is a passport. Even the manager is likely a fairly low level employee who knows only what she's been told, not what the law really is.
If this is the first time in three years you've had any hassles, I'd say you are probably not going get hassled much in the future.
You could just get a California drivers license. I think you are supposed to anyway if you reside here more than a month or two.