[MichailP]

If my evil :) speculation is true, the camera sensor is just picking up mechanical vibrations from environment (coming through air, tripod etc.) and encoding them into video. There is no proof that the bag of chips is vibrating (they even say that the vibrations are not visible on footage). They are extracting something from video, but that something may just be spuriuos pickups by equipment, and not related image/video of bag of chips. Thus it would be just a silly way to measure spurious mechanical vibrations.