I'm sorry I can't see anything now!

When did it become socially acceptable to not dim your brights to oncoming traffic while driving at night?
I was driving back along highway 7 last night, one of my least favorite drives in the world. It's bad enough that it's dark, there's no towns until Welsford, no lights and then there's threat of moose jumping out at you at any moment. And once the fog hit, I seriously couldn't see anything and started to drive like an old lady (and really couldn't care less that I kept getting passed, the red lights gave me something to follow)...but the number of people who did not dim their brights as they came along the road astounded me. At first I thought it was some random thing, but it became more and more apparent that their ability to see something was more important than blinding the people they passed along the way. Strange.