RFID with EAS

So if the item is sold at the POS but a EAS/RFID tag is left on, is the system smart enough to know its sold and not ring? Or maybe have a different sound of alert to tell the front end employee THIS IS SOLD BUT THE TAG WAS NO REMOVED.
My point is why will RFID/EAS do that current EAS cannot.A RF frequency tag will always set off a system. I am curious if the action at the POS can alter the outcome at the door. And why use hard tags? go with something embedded no? Make it employee labor free.Isn't that the point of all this??