That's why they went with $650 too. While we all know it would be more attractive at $550, if they sell out all of their limited stock anyway then pricing it any lower would be them throwing away money.
It does hurt mind share a bit though, as many see AMD is idiotic to price it the same a 980 Ti when it is slower.
Finally someone with a business sense!
You always price your products at the highest point the market will bear. AMD being able to command $650 from the Fury X is a very good thing for AMD. Demand still outstrips demand, and AMD will do their best to make the most of that situation.
AMD is probably keeping all but the best Fiji cores for Fury production and we don't know where the pipeline bottleneck exists, it could very easily be the AIO and potentially more so due to pump revisions.