Just because something is common among the masses does not make it correct. A large percentage of people who don't shoot regularly still use a teacup grip when shooting handguns that does not make it right. Things change, we learn and we must change if we want to grow.
As to the use of lights on your defensive weapons. If you live on this planet you experience a 50% light to darkness ratio whether it be hours, days or weeks (dependent on latitude). It doesn't have to be pitch dark to be unable to identify a threat. And I don't know about you but nearly every crap situation I've had come up in my life has been at the worst possible time lol

