I'm on my third Subaru. (Two Legacy wagons that each bested 350k miles, and now my Impreza wagon is about to hit 300k) I learned about this switch very early on, but then it was called the "Subaru virgin switch"
I even heard about a guy that claimed to have bought a few Subarus really cheaply (due to the "electrical problems), only to then turn the switch off after driving a few blocks... (seems dishonest to me)
As for why these lights would not turn ON... That may likely be a completely different problem. Unless, of course, the Previous Owner had hacked into something to get them to turn off... (?)