I think it's the law here in Jersey.
Just came back from trip to Massschusetts. We were driving home during a very heavy rain storm and was so surprised that many cars did not have their headlights on. It was only 4pm but the sky was dark grey and with the heavy rain it was difficult to see some of the darker colored cars. DH got off the major highway we were on as we were sure there was going to be a major pile up. Took a local highway until it stopped raining so hard and happy that we made it home to Jersey in one piece. May in Jersey