The airport doesn't look like it averages all that busy, the vehicles on the road are probably used to not seeing any planes on final. They should have a stop sign with big works that say LOOK for planes.
The student was low, possibly in part to do with training to not land long on a short runway. No, not an excuse to be that low, but not wanting to roll off the other end either. Just another set of events that line up to lead to an accident. At least no funerals to attend.