Has nothing to do with riding at night, jerks will be jerks 24/7.. I have actually had the opposite during night rides, just a lot fewer cars on the road to harass you. It doesn't pay to say anything back, you will just be giving them what they want. Politely wave and say have a nice day and you will be the better for it. Last time I checked 3000-4000lb car always wins against a 22lb bike.