That's the default assumption for any site/sale that only shows prices in USD.
No. If there is a statement that they accept payment in bitcoins and they quote a price in bitcoins! If customers select the bitcoin payment option then they are offered a price in bitcoins. So, in case of a refund they must get back the same amount in bitcon they have originally paid.
-Product was paid for with BTC.
-BTC were not converted to fiat and keep in one wallet.
-Refunds for those who paid with BTC are now getting lesser BTC back.
-Somebody is doing the calculations.
-Who? and Why?
If I were to start some fictitious entity that sold pre-orders for some product, and accepted and amassed Bitcoin, with the hope of bitcoins to increase in value, this is the way I would do it. After a period of time, whether the price goes up or down, I fold. If it goes down, I'm out very little and time when I return all bitcoins. If it goes up, I return the dollar amount, thus pocketing the profit. In this case, it's averaging about a 20% return, on how many bitcoins? The CC charges will be handled separately or I wouldn't have accepted any. If I operate as a crock, not only do I get to keep the 20% profit, but I would also not pay back all the vendors and play catch-me-if-you-can.