A five-kilometer beam would not illuminate only its paying customer. Scattered light could reach nearby communities, habitats and roads. The exact reach would depend on weather, atmospheric conditions, brightness and how the mirror is aimed. Flashes created while a reflector changes direction could also distract pilots or drivers.

It’s annoying enough when my neighbor’s motion sensing porch light keeps turning on. This sounds horrible.

If someone were to aim some spotlights at the employees’ houses all night, which nobody should do, it would make interesting news.