When I played I just spoiled the data. I found out that you can just hold a white piece of paper in front of the camera and bounce your phone lightly up and down to simulate movement (since they want you to walk around the real world location you’re photographing). Other persons I played with just photographed their shoes, so Niantic only had useless photos.

I’d guess the majority of players properly adhered to guidelines when doing AR field research. A small minority probably uploaded useless data.