How can they do this and make money?

"100% Insurance from today until the end of the month for deposits larger than $25!

Club Gold Casino will pay you back everything you deposit from today until the end of the month, in February.

Simply come and play the casino everyday and you'll get 100% insurance on every deposit larger than $25 you make!

Yeah you heard it right, we at Club Gold decided to do something out of the ordinary, so we thought of taking the risk out of the games with the Casino insurance. You are totally covered.
 
If you hit a zero balance, we’ll pay you the insured amount, directly to your account.
That`s right. Say you deposited $300 today, you will get it back in the first week of February.

At Club Gold Casino, there's always a chance to win your pile of Gold. We'll see you there!

Have fun!"