What are the consequences of a correct answer!
Another case where the answer to the "Could anyone of interfered with your bag since it was packed?"-question would have to be yes, is when transfering from one flight to another where your bags are not checked through:
IE A routing fromsomewhere-STN with Ryan Air to be followed by STN-somewhereelse by same company.
Flying that route you would have to answer Yes to the question!(the bag will have been out of your sight for hours in the hands of who knows!)
Then what happens? Do you unpack your bag in front of the check-in-guy/gal? Extra security check????