Early passports had two picture slots, the other being a photo of the back of your head, these were brought into force by the constant swarms of illegal immigrants making a run for it upon being discovered, and custom officials only being able to recognise them from behind, which in due course made it a lot easier for them to identify them.
However, after the rise of Swedish porn stars and footballer`s from the 70`s and the introduction of permed mullets, the crafty asylum seekers begin to follow suit and sport similar hairstyles, and the more astute would brush up on the lingo "If in doubt, whip it out", "Over here son, on my head", "Get it in the box early", others would learn some football quotes too.
The only people who didn`t need to use a dual picture passport were members of royalty, whom only had to lick the back of a stamp and stick it on the passport, this was a constant nuisance for King James though, as every time he done this, he duly posted his passport in the nearest letter box.
So, in the nutshell, the reason we need to post backs and fronts of things are ugly girls with fantastic asses, and nothing to do with 70`s porno and football stars at all.
Hope this clears things up
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