I recently had laser eye surgery. When I drive at night there are halos on every light I see which compromises my depth perception. I can't pick out the important lights as quickly as I used to. Still, I always notice flashing bicycle lights.
So you're out driving on the highway in pitch darkness with hi-beams on and another car appears in the other direction. Is it not common courtesy to turn off your brights when they turn theirs off? I kill mine when theirs have made it difficult for me to judge where the road is.
I thought it was bad when driving! Only one in thirty vehicles turns down their brights at all when I'm on my bicycle. I absolutely could not SEE commuting in the dark just because of that (well, and the terrifying transport trucks whose drivers weren't expecting bicycles on a country road in the middle of nowhere).
Even with the brightest lights I could find on my bicycle I have people tell me "I almost ran into you. I could barely see you."
Safety first, kids!