No, the mic is placed in a position that is close to where you would listen to the music (ie about your head location) and it sets a single global EQ setting based on that one sample.

If you placed the mic near a speaker, you would only get a nice EQ for that speaker, not for all the other speakers and not taking into account phase, reflections, and the upholstery soaking up frequencies.

If the mic is not omnidirectional, then it's almost as bad as sticking the mic in front of a speaker, i.e., it's not behaving like your ears behave and won't give as good of an approximation of the overall sound of the car's interior.