Bitcoin Shop - question
Their wording is a little funny but it sounds like they act as a middle man and cannot guarantee a price until they have facilitated a deal. I assume the conversion rate shown on the main page is only an estimate. In that case they don't have to worry about price volatility as they are putting that burden on you the buyer.


  §4 Terms and Conditions of Service
  
  The Service uses the services of online payment provider Dotpay S.A.,
  whose office is located at ul. Wielicka 72, 30-552 Cracow, Poland.
  
  Using the 4Coins.pl via online payment provider user transfer funds to
  the 4coins.pl’s account in PLN currency. The amount received by the
  Service is reduced by 1.9 % of its value as a commission charged by
  the online payment provider.
  
  Service under an order for the total service credited to the account
  searches offers on the market BTC – bitcoin and mediates on the
  principle of matching user with the available range of offers.
  
  Due to the nature of the market BTC website does not guarantee the
  execution of transactions on the presented course. Given course is
  presented only in the form of information.
  
  After the service, the user will be informed about the parameters of
  the transaction, and may order the withdraw of their units BTC –
  bitcoin.