Signs of the Obvious

Why do we pay for expensive traffic signs that tell us what we already know?
Observe:, an "End Road" in front of a brick wall -- Why, yes, we got that.
“No Center Stripe” – Why, yes, we can see that.
“Gravel Road” – Why, yes, we can hear that.
“Unmaintained Road” – Why, yes, we can feel that.
“Use both lanes during backups.” Uh…who’s struggling here?