Theoretically, if everyone paid KnCMiner in Bitcoins -- approximately $7 million so far -- shouldn't we start seeing some pretty large BTC sell orders on MtGox soon?
ASIC manufacturers, namely BFL and KnC (though also Avalon at one point), all utilized BitPay (or similar service) for Bitcoin based transactions. What this means is that those companies never saw/received a coin...it was instantly converted to USD (or whatever other currency) at the market rate at the time of purchase.
Bitcoins --> BitPay --> converted to cash --> Manufacturer is paid (and BitPay takes a cut).