Maybe because I've had to work on enough remote consoles without any, or limited, color support where I'm more concerned about the problem at hand than which shade of blue is being output for directories. Ok, I'll admit I adjust the default apple terminal 'pro' scheme colors a bit, adding a bit of contrast to the background because I'm in it all day, but beyond that, nothing. I find coloring has little to no positive effect on my productivity, and in some instances, hinders it. No colors on ls, I actually get a bit annoyed when color escapes reach stdout via logs now, hah. Hell, that extends even to my $PS1. I've never bothered to update it on this system. Crotchety, grizzled ops person perspective maybe?