I spent a large part of my childhood in far north Ontario (as in at least a day of travelling to get to Sudbury!) and I completely took them for granted. That's just what the sky looked like when it was cold.
I didn't grasp that this was something unique I was experiencing. I'm sure there were nights they were that vivid. I remember more blues and purples, though.
I haven't seen them since I've been an adult, since I've been old enough to appreciate it. I've been thinking about taking a long weekend trip up to Yellowknife one February. It's actually not too bad from Calgary, cheaper than going to Toronto.