The Pokémon Go data is for small little islands around their points of interest (pokestops).
That's not the impression I get from the TV ads.
The ads they run show people walking along sidewalks and through forested paths and through parks in AR mode.
The controversy elsewhere in these comments is over whether it’s recording, and the server is slurping up, the video footage, during AR mode. We know they do so on the “scans” they have you do, where you walk around something taking video, but I don’t think there’s proof that having AR on = uploading to the server. Should be easy to prove one way or the other by observing bandwidth usage.