I do not think that's unique to just the ESS versions... I thought the same thing when I bought mine last year - it was the quietest vehicle I've ever owned re: starting.
REMOTE starting, I had to look out the window to be sure I could see the lights. All other cars, I could HEAR them crank-over and idle - not loud, but perceptible in the quiet hours of 4:00 a.m. - not the Pacifica... I need to give a visual check.