Trying to understand the "back roads" part of this. Are you talking about pulling off the highway onto a farm lane or forest road, and parking alongside or in the road? Or backing into someone's access to his field?
In most of the country, U.S. numbered highways, state highways, and county roads are all highways (even if you are personally inclined to call anything not an Interstate a "back road") and you usually have to clear the right of way if you want to park. If the road is patrolled at all, your parked vehicle will be checked out for possible emergency situations, though you may not always be told to move along.
We've pulled off the road to overnight on farm roads, after asking. Parking lots are a possible option in small towns, unless the use is posted, and you still may be rousted, because small town people tend to notice anything unusual, and in small towns the parking lots tend to be where drug deals are made.
The access roads for oil well and tank battery service, pipeline roads, service roads to wind generators, power lines,and mobile phone towers will look tempting, but are almost always posted and are often watched by remote video and there will soon be someone out to see what is your mischief.