This happens more often than not on my trips through more rural areas (once, it sent me through a muddy corn field to avoid a traffic jam on Christmas night in rural Louisiana -- fortunately I understood what I was getting in to and had a vehicle equipped to handle it), and I've noticed it seems to have more to do with people who have google maps keeping their phones with them.

That is to say, it tracks where people drive, and when people drive in the same place often, it flags it as a common route and therefore must be a road! I have a hunting lease in rural Texas, and the most common trails within the property are all highlighted as roads in Google maps. In fact, as I cleared out a trail a year ago and started using that trail as a way to reach one point on the ranch, it has now also become highlighted!

You'd be a fool to cut someone's locked gate to take such a route, but it does offer them as routes to me were I to ask how, for example, to arrive at the entrance gate of the property north of us. The only legal (and passable) route is actually to go south, then east, then north, then west. However, google maps says "Hey, just take this trail straight north."