I dont think the sensors would detect any movement unless a problem happened. The wheels don't rotate and the movement does not seem to have acceleration high enough to trigger the alarm. Many alarms today don't even get triggered when the car is hit by a ball, for example.
This is interesting (never had an annoying alarm)! Seems sound waves create more disturbance for the sensor than an actual blunt impact which is localized to a point on the body and possibly not transferred through the chassis to the sensor.
