It's amazing how a change in technology can change behaviour: even though the day job is associated with hte lighting industry I still find it difficult to grap the changes that LED lighting are bringing to people. They use so little energy that whether you've got them on or off, or whether you use them year around, really makes very little difference. In this they're quite different from incadecents, halogens or even fluorescents.
For example, a string of 2,000 LED christmas lights can be left on for 8 hours a day, 365 days a year, and the total cost in electricity will be about $50. 13 cents a day, or if you prefer, less than 2 cents per hour that you have them on.
It's almost not worth reaching over to turn them off at that price, isn't it?
And at that price, you could use such lights for much more than just the Christmas decorations.