You should also bear in mind that provided they stick to only
projecting images onto the cloud base on cloudy nights it has
almost no impact at all on amateur astronomy. If they only use
it on cloudy nights no harm is done.

Martin - you mean "...no harm is done *to astronomers*"

Of course, the lights will destroy the natural night time
environment, leading to confusion and death to countless number of
birds (www.flap.org), thus encouraging the scavengers like rats to
survive.

And if the lights distract motorists, they could cause a fatal
accident (as have happened a few times before).

cheers,

Das