Lads ... calm down.
In most cases this is being dealt with by people with some skill and tact and you are hitting the rare cases. Certain airports mentioned above have the toughest scanner detectors in the world
if you are going BA JFK-UK then the when passing through the terminal they are calling for all shoes off - this then causes things to go faster rather than having your shoes rescanned [which happened to me]
Security wins over dignity every time.