DAE stutter more in front of people you are close to than strangers?

DAE stutter more in front of people you are close to than strangers? At home, I stutter a lot while at school with friends it is a mild stutter but still problematic. However I have no problem whatsoever (I.e. very mild stutter) talking with strangers or on phone. The only exception to this is when ordering food in person at some fast food joint. Why is this?!