So if they start telling people outside the realm that they're elves, they automagically become human when they leave? That'd sure make any RPs between Sirion and other realms look absolutely stupid. 
I'll just ICly chalk it up to lunacy.
Of course its Lunacy. Lets look at it this way, the stereotypical fantasy elf is part of a empire that is past its prime. They spend their days remembering the glorious golden age of their empire, with little or no chance to ever reach such heights again while they wait for the pitiful remnants of their culture to finally perish completely. Its complete Lunacy to want to buy into that.
