Umm, if someone wants to start a business of filling real bottles with fake juice, they'll figure out a mechanic, there are much more high-tech complex scams that go around out there. Detaching a cap and then reattaching it is by no means very high tech. At least most caps I got seem to be easily removeable. (that's the top part at least, the bottom part is not, but I can see a way around it).
I doubt they'll fear people will just buy the refillable juice. Honestly, if you're throwing $200 on juice, you probably would like to have the $50 presentation on your shelf as well. I honestly think as simple as this; there's no demand for it, especially in the middle east, not only refilling is not a popular marketing strategy as it is in the west, Amouage are relatively cheap. Also, the idea of a "Signature fragrance" is not common in the middle east. Middle easterns might buy more perfumes, but most of the ones I know would always ask me "why would you buy the same juice twice?" It's sort of like fashion, if you bought something, wear it for a year or two and move on.
So, ultimately, I just think there's simply no demand for it.