You kind of answered the question in your first sentence. The real version costs so much what's the point of buying a real one. It's actually smarter to buy a fake watch, I've been on fake watch forums and communities and let's just say most of the people there are pretty well off. They're just smart enough to know that the watch is simply for show. Why buy the real thing when you can get the same reactions wearing a fake one for 1/100th of the price. Most of these rappers with fake shyt know it's fake. Obviously they never knew somebody would make an instagram account "exposing" them but I doubt it's going to stop them from doing what they do, the bytch in the club Im trying to impress doesn't know how to differentiate a real one from a fake.
Well, for one, if I had the money I'd buy a real subplot, not just for show but also to celebrate myself being able to earn one, and I can't act like watches don't take a high level of craftsmanship, one that I don't understand at all.
As for rappers, man I'm not going to say that they're out there buying fake watches because you have to keep in mind these dudes are from the ghetto, do you think they'd ever imagine having a $70k watch? I don't think so, so they don't even know much about the watches themselves except for the price and what is told to them by jewellers, who may take advantage of them because they know the rapper will be blinded by the diamonds.
Either way, rappers stop putting fukking worthless diamonds in watches that are already worth thousands of dollars.