I don't know why more people does not mention their 0 confirmation policy for bitcoin. I don't know any other site that is letting players bet in the same second they send tx before it even confirms once. Great thing with no actual risk attached (you can't withdraw winnings if your tx does not have 3 confirmations).
It is hands down the best feature for me, very easy to implement and yet only Sportsbet has it.
It's a great feature, and more gambling sites should implement it as soon as possible. By accepting a zero-conf transaction you show your customers that you trust them. And it's a nice feeling when the people you are dealing with trust you. You want to do business with them again and again.
As you have rightly said, they are covered against losing money. And that's good, because not all people can be trusted. But for honest people it's a good bonus: to not wait for a confirmation.