As mentioned earlier, it's not all about a loud vehicle but more about the driver/rider. A loud vehicle at cruise is a lot less annoying than one that is being throttled; case in point, Harley riders who think it's cool to blip the throttle every time the clutch is disengaged and continuously blip the throttle while sitting still...obnoxious noise for the sake of noise. Learned behavior.
Get this a lot in my sub. It's annoying as hell with young kids who are in bed by eight. My car isn't quiet by any stretch, but if you idle it to the house it isn't bad.
