Why should running off the road and destroying private property be a totally
risk free endevor?
What percentage of drivers who mow down a mailbox actually stop and offer to
reimburse the owner?
A friend of mine couldn't keep a mailbox, until he put it up on an 8" box beam,
poured solid with concrete. The next guy who hit it tried to make a case ...
until he pointed out the 25MPH speed limit sign next to the box and measured
the skid marks.
You have no legal obligation to make things on your property idiot safe, in
spite of what an ambulance chasing attorney may try to prove in court.

Shakespear had it right "Kill all the lawyers".