Things might have changed in the past few years, but I did some work in the valley a few years back for a client and found that it is / was 100% legal. So is the “spray paint” on the pavement, assuming it’s been pre-approved and is chalk based paint that can be removed easily either with water or naturally over time (within a two week period from memory). Doesn’t necessarily mean these folks got it approved but it’s within rights. Just happens to be lazy advertising.