They know exactly how much they'll pay before executing withdrawal. If they position slider to the left, they'll pay 0.0006 btc, if they want fast withdrawals, they'll slide it to the right and pay 0.003 btc. It's player choice how much they'll willing to pay for withdrawing their funds.
I'm sorry, but I think you're missing the point. It's less about the fact that the site is charging higher transaction fees. It's more about, based on reading the FAQ/blog, most players/investors will assume the slider gives full control of the actual fee paid, and that it's totally dependent on network conditions, with crypto-games taking no cut, but that's simply not the case.
Reading below (From blog):
Example: I paid 0.0008 BTC for withdrawal fees, but blockchain shows it was paid less, why?
In this example we paid 0.0008 BTC fees per one kB. It is not possible for us to give good estimates, or an estimate at all, of how large your transaction will be. When a transactions size is lesser than a kB, the transaction fee is lower than 0.0008 BTC accordingly. Same goes to different amounts.
I can't help believe this is cleverly worded. It could mean:
1) The transaction fee sent to the blockchain is lower than 0.0008 (which means nothing to the user, and is irrelevant)
2) The transaction fee charged by crypto-games to the user is less than 0.0008 (this is what actually user thought should happen based on that wording, but doesn't).
This is a CLEVER way to charge users more without them knowing it!
I think I've made my point. No transaction fee size is 1kb, therefore your fees are significantly higher than other sites, well to be exact, over 10 times higher than Yolodice for lower fee per kb, therefore I'm going to have to agree with jpcfan. Being 10 times higher (although not ideal, but a separate topic) is not a problem in itself (ie you have other benefits like lower investment commission), it's hiding this fee in a confused fee/kb scenario that is a problem --> Most users wont think they are charged higher fees but are shocked when they see the txid.
Now I see two potential replies to this post. 1) I'm wrong (and telling me why) and I shouldn't bother to play on the site anymore coz you don't care, or 2) You've listened to me and take my point and may possibly look at the situation. I hope it's 2) but I think it will be 1)