No logic works with the security numptys but try "discrimination" as a way to get back at them.
I have a large amount of metal holding my leg together, as you might guess this plays havoc with the metal detectors. If they get a little too heavy with me I always call for a supervisor (an equily stupid long term security person!) and say that they are discriminating aganst the disabled, remarkably this "PC" tack has an instant effect on them.
Please never get abusive with them and if they get that way with you politely point to the notices about abuse of staff and say that you demand to be treated with the same respect, that will have the effect of enraging them to a point that the whole thing becomes a farce and they have to call out the real boss.
The name of tha game is to keep cool in the face of this utter stupidity and bounce the problem as far up the command chain as you can.