just an assumption, but my guess is that you'd be using the fake glasses in order to attach stealth mic's, yes??
what i do is wear a pair of sunglasses on the top of my head, you know, ear pieces on the ears, but glasses on the crown of your head type of look. use a croakie, too, they act to stabilize the glasses so that they arent so floppy and loose.
this accomplishes two goals: i'm not standing there holding mics in my hand, and the mic's are now 4 inches higher in the air, hopefully getting better sound.
anyway, my solution for what it was worth.
i'd say its a better option than paying $30 for fake glasses; instead spend it on a pair of shades that you'll use at the beach or wherever ....