evyjet, the problem is the people that make these rules really have no idea what goes on at the front. And these piloting armchair experts are even worse with their tiny bit of knowledge on the topic.
The best thing is to just go along with it play the game. And if i tested for explosives or whatever i'd just go along with their process as its not worth the trouble (you might get tazed!). Like that everyone (joe public armchairidiot) can feel all safe warm and fuzzy.
I must say though that i find most people are quite polite and haven't had a problem. Its just the system thats stupid.