Originally Posted by Wulfheir
The alternative is a cyclist with no light not seeing you and throwing ~200lbs into you travelling @ ~20miles/hour. Be thankful you only got a spotlight in the eyes, instead of a stem in the nuts.
While I don't advocate intentionally blinding people [mostly], MUP can be death zones in the dark. I've heard many a tale of pre-dawn rides that involved bunny-hopping passed-out homeless people on the river pathway system, or the blind corners over by the zoo where walkers pop out of nowhere on the wrong side of the path. Lights are good.