It wasn’t all that long ago that they were not covered up. Started by homely wives of powerful Islamic leaders? Husbands were looking to add pretty girls to the haram?
A significant portion is economic in nature. I knew a military guy that did economic espionage. He would just walk into places like he belonged there. A function of badges and guile.
Actually it is the survival of the sufficient. And with the modern world the sufficient bar has been significantly lowered. To many’s chagrin.