Seems that a lot of you live in some sort of crime free shangri-la.
1/Surprisingly, opportunistic thieves take holidays, business trips, etc. just like the rest of us.
2/This morning, I spent circa ten minutes putting my shoes/belt etc back-on, putting the laptop back in the rucksac, etc., at a major European airport, happily watching the contents of everybody elses luggage on the very visible screen. Nobody tried to move me on.
Put 1/ and 2/ together, and it's almost inevitable that an opportunistic thief/thieves will use the information they might glean at security to not-so-good use. Airports, railway stations, public transport generally, are perfect hunting grounds for pickpockets and other diversion robbers.