And lightning does strike, some times, some places. Putting fences around every tree to keep people from hiding under them would save some lives. But in this c

And lightning does strike, some times, some places. Putting fences around every tree to keep people from hiding under them would save some lives. But in this case there's a rather large negative of being trapped. It's not enough that there be some theoretical benefit, but that the benefit outweighs the costs.