Contractors in California bay area without contractor license # or name on vehicles?

[Matt A.]

Why is it that so many General Contractors in the California Bay Area drive vehicles that don't display their contractor license number or business name? Aren't they required by law to display these items on their vehicles? I think "California Business and Professions code 7029.6" is the name of the law that requires them to display this?

I ask because I've interviewed a number of general contractors over the years for my various real estate projects and am shocked at how the vast majority showed up to the job site to give an estimate in a vehicle that did not display their contractor license number or business name.

Aside from this one issue, they'd often have great portfolios, long list of successful permits I could verify they pulled, great references, no complaints on their license, and had been licensed for over a decade. It made me wonder why they would not follow code 7029.6. Perhaps there is a reason I'm not aware of?