They all look legit to me, even those "cheap" Chinese ones ... Sorry, but I have yet to see any evidence of fakes even existing. Clones are a different matter.
AFAIK Cherry require a large MOQ for switches (300k or so) so even the prices you see on Mouser, etc aren't really "bulk" prices like you could get from a warehouse big enough to buy massive quantities (like some chinese warehouses) or have a deal with Cherry. If you are making 104 key boards with LEDs, steel plates, good PCB, nice keycaps, etc, I doubt you can affor to spend $100 just on the switches and still make enough off the sales.
They are made in different factories with subtly different molds, but all the switches I have seen so far that have the Cherry logo on seem to be the real deal.
So... anyone with real evidence of fakes please present it, otherwise please stop giving credence to a rumour.