I'm too lazy to find the statute atm but any vehicle that is legally allowed to use flashing amber lights (parking enforcement, tow trucks, roadside service, etc) is allowed to block otherwise unlockable areas like red curbs or bike lanes or even an entire lane of traffic as long as the amber lights are flashing. The light color designates them as service vehicles that are separate from emergency services (red and blue) but above a standard passenger vehicle.

Obviously it's bad form to use these lights to run into a store to get coffee or lunch or something. But if they're being used while doing legitimate roadside service work it's legal. As far as the law is concerned, it's a legal form of the "park anywhere lights" that many drivers seem to think their hazard lights are.