IIRC many of the original employees were ex-Googlers and the original Ingress game did use Google Maps data so at some level they were able to get what they nee

IIRC many of the original employees were ex-Googlers and the original Ingress game did use Google Maps data so at some level they were able to get what they need. I think there were rumours about them using undocumented abilities too in the early days, but my memory is fuzzy at this point. They moved to OSM later.