Originally Posted by
HeyNowSkippy
The scan is their version of the stub they keep. Go into the United app and tap Track My Bags. You'll see they have a record of it. I'm fairly certain they do this with green tags.
Never saw any bag tracking for green tags.
My guess is GA doesn't know whether pax has the other side of the stub or not still, so easier to just put on a new one and hand new stub. I have warded off the new green tag by showing I have the stub still.