I believe Bidfire uses bot bidders. If the "bot" wins, then they do not lose the money on the item auctioned. It is simply never sent out! Therefore every legitimate bid on the auction is pure profit.
I recently bid on item, watched the clock end on zero with my bid as the top bid, and as the winner was announced, it showed the only other bidder as the winner! The clock did not reset to 30 seconds as it was supposed to. Very fishy indeed, so I am suspecting the "bot" algorithm had an error. Even if the other bidder was legitimate and not a bot, the fact that the auction ended with my bid as the top, and yet the auction was given to the other bidder is not right. I am extremely suspicious. In addition, they acknowledged the error, but did not honor my win, instead refunding me some bids. I feel they should honor the win, but I'm not holding my breath. I will update this review if they do.
Yes, you CAN win items, but if they are really using bots, which I suspect they are, you are nearly assured of losing money or losing the auction.