Well if they drive past a McDonald's or other open WiFi, presumably it'll get uploaded then right...?
I haven't been to MickD's in a really long time, but do they have free/open wifi with no captive portals? Seems like a big liability risk for a corp their size (or any fast food chain) to have it wide open.
I know some Arby's are semi open wifi. They do have a web client after connecting that I think authenticates you somehow. But I have no idea what it's actually doing.
That would be a way larger security risk.