I know that Canon has outrageous pricing on their WFT units. They seem to think that the desire to use them is among organizations like Getty images and such, where quite a lot of money is tumbling around anyway.
Regardless, they work well. I like the higher level WiFi implementations (not those built in to some lower spec EOS cameras, but those provided by the WFT accessories), since they can do FTP transfers of images on demand when you shoot. I frequently use that when I use my own camera at work. Connect camera to company WiFi, run FTP server on my computer in the office, take photos out in the workshop and when I'm back in the office the images are already in my computer. Very handy. Totally not worth the cost, but very handy.