Bugs provide protein. You gotta learn to catch them in flight. Rocks provide minerals. Facial scars provide machismo.
Just smartazzin here...

This discussion will never have a resolution. It is up to the individual as to what risks they are willing to take. If flying vermin and road debris are a problem, you do what suits you best. For me, the benefits of experiencing the open road outweigh the occasional gobsmack from an errant insect.
But that's me....