1BTCXE is a true multi-currency exchange platform. Users can place orders in any of the various supported currencies using a single account. All orders are combined into a single order book even though they may have been placed in different currencies. This is done to guarantee liquidity for users in all supported currencies. 

When converting orders into your native currency (the currency that you are currently using to view the site), a currency conversion fee will be factored into the price that you see for that particular order and the order will have an icon indicating the currency from which it was converted. This fee will only be collected in the event that a transaction actually occurs across two different currencies.

These conversion fees will cause converted bids to seem cheaper than they actually are, and converted asks to seem more expensive than they actually are. Therefore, if a trade occurs in a different currency (or currencies), the orders involved will actually be at the top of the bid/ask list in their native currencies - but not in yours. This will cause the last price to be outside the bid/ask spread for your particular currency.