So People Actually Believe this BS?

A buddy of mine had his windshield pulverized by a large construction truck this morning and right before it pulled away he grabbed a picture of it on his phone.

Turns out, he apparently wasn't going to call his insurance company or the construction company because he thought the "not responsible" sign made these trucks magically excluded from the law.

Are there people out there who actually believe these signs make these trucks any less responsible for causing damage to other vehicles?