But I agree, if I was confident there was something wrong with it, I wouldn’t use it. OTOH, you have a practically brand new car, the dealer will look at it for free as many times as you like. So, before letting this upset you, perhaps consider a professional diagnosis. The system is pretty simple.
….even at half throttle, the car did not budge. But, if it had, I would have shot out backwards possibly causing a crash or worse running over a pedestrian.
Perhaps it varies (doubtful), but it takes only the slightest throttle input to trigger the EPB release on my car, far less than what would be required to really get it moving (the pedal does have to be depressed very slightly before the throttle begins to open). I’d expect this would be the case on every Outback with a properly functioning EPB system – you should never put 50% throttle against the parking brake. Like I said, if your seat belt is properly fastened (and the belt sensor is working), it just takes a little nudge on the pedal.