Yep, you missed the point of the argument! Well done!
It's not the object, it's the principle. It's one more place where the Gov wants to infringe your rights and try to frighten you. What next? Scanners in every supermarket, Dentist, Doctors, Fire Station, Ambulance station, school....then finally when everyone is being scanned in public places, next is your house, finally your bedroom. Then once they can check on every single person, all the time, the world will be safe and everything will be wonderful, just like the idyllic little world you seem to think will come from scanners at airports.
The Gov wants nothing more than to ID every citizen, tag 'em and trace every single movement, ideally a little brain scanning just to be sure. All a little Sci-FI I grant you, but if they had the option, someone would be willing to sell this nation down the Big Brother road a little further to line their pockets.
Just to prove these things are safe, lets insist that the MPs backing it and the directors of the scanner maker companies have these things installed in their offices and homes, just for the next 12 months, then if they are ALL happy to do it, then I'll think about accepting them at airports until then F.O.A.D.!