I think parent is saying this would be an interesting way to mine a population for marks that could be espionage targets with easily identifiable special needs susceptible to temptation by foreign entities for nefarious goals. Did I make that obtuse enough or what? :D

Because there aren't 100 easier ways to achieve that?

But then where would all the cool historical spy movies come from as time passes?

Blackmailing officials who have done something shady or embarrassing which has not yet been detected by the local authorities or the press.