The liability issue can be huge. I would imagine some of the rules are a result of the insurance carrier imposing their own rules as a condition of coverage.
A range here in the Austin area experienced a nearly tragic incident a couple of years ago. A doofus, wanna be gangsta was shooting rapid fire with his AK and sent some rounds over the berm at the 100 yard line. About a mile away a pickup was driving down US 290. The truck caught a bullet in the windshield, through the rearview mirror, out the back window, hit the tailgate and fell out the slit between the bed and the bottom of the tail gate. Driver was narrowly missed but did catch some glass in the face (nothing major). I made the scene and started looking at the map and the range layout. found that the range was angled toward that spot on the road. By the time we got to the range, the dumba$$ had departed. That left the range owner holding the bag. He had no records of names of shooters to fall back on. At the time he did not have an employee actually standing watch to control the range. That range is no longer open.