Presumably your radio/TV/music player would have to be in the loop so Luna didn't mistake them for you talking in your sleep?
Surprised if people still get out of bed to do anything with lights. Bedside lamps have been usual for decades.
It is obviously useful for the alarm not to interrupt deep sleep - or even to pre-empt you entering that phase too late. My alarm wakes me about once in three months if I've had a particularly late night - otherwise I'm usually awake before it would go off.