GPU prices are all over the place at the moment due to things like mining - some have simply been priced up and never adjusted others have been bought in at a higher or lower price depending on fluctuations and the retailer can't really afford to adjust that price, if the overall market adjusts down, until the stock bought in at a certain price has sold (or they are forced to drop prices if stock hangs around long enough).
You definitely have to shop around at the moment for GPUs due to this - I've seen base model 1070s in some places more expensive than OC model 1080s, etc. (probably due to the comparable attractiveness for mining at some points in time).