I was checking in using Curbside @ the CO terminal at LAX on Sunday, a car pulls up and a guy gets out and gives his bag to the guy in front of me (they appeared to be buddies). The guy in front of me says to the sky cap, now I have two bags (the guy who gave the bag from the car had to leave to go park his car) and the sky cap asked him the two questions of which were
1. Have these bags been out of your sight? Reply "NO"

2. Have these bags been with you since you packed them? Reply YES

In both replies the guy answering the questions appeared to have a little smirk on his face as he answered them

the sky cap looked at him funny and took the bags, tagged them and checked them in

That is why we have a problem. It was done right in front of the skycap and he took it anyway