Bitmain does not accept BTC for miner payment, only USD and LTC. I wonder whether they think BTC is too high though it's interesting .
When I go to Bitmain, the prices are in US$, BTC and LTC.
If you try to purchase a psu and checkout. It only gives you usd wire or litecoin. In the past they have stopped accepting bitcoin when there was large swings in price.