Decreases security and safety. Causes global pollution. Obliterates beauty of the night sky. Current lighting fixtures create widespread problems. This picture shows a typical widely used light.
Unshielded lights create glare.
Glare decreases visibility. Unshielded lights pre expensive. 35-70916 is wasted by going up in space. Wasted energy contributes to unnecessary global pollution. Unshielded lights cause light trespass into one's own home and violate privacy in others'.