And I blamed Paranoia.

Every time I go to bed I see the houses across the School Field all lit up. 
I wondered why, when, so far as I know it's the back of them, here being only a Path barely wide enough for two folk to pass.

I finally took the Camera to bed (Not my Camel) and discovered that it seems to be the local council's "Street" Lights, rather than the inhabitants'.
Must require thick curtains - they were still on at "Piddle o'clock".