Yes, because that's exactly what it is designed to do. How do you think it would work in parking mode if it had no supply?As there is no black box does that mean the cam is consuming 12v when engine is off?
Incidentally, it doesn't 'consume' voltage, it 'consumes' current (Amperes).
A good analogy is water in a pipe. Voltage (V) is the water pressure at the feed end, current (I) is the flow rate, and quantity of water in a given time is energy. The diameter of the pipe is roughly the equivalent of resistance (Ohms) in an electrical cct.