It is indeed free, but it does have an interval after you claimed once,, and using free satoshi in a certain gambling site is good if you are just playing gambling just for time, though it will not last that long because that is only a small amount of money, and making profits out of it is so hard since the house always win. Using that is a safe way on how you are going to explore the game you wanted to play in gambling before you use your money on betting.
Yep faucets are free and this is one of the attractions that the casino's have. There's a time interval so that they are not going to be abused and if you are all aware of primedice before this is one of the hottest casino's before that when a gambler decides to stop dicing because his full attention is getting close to the faucets that has levels of claims. If someone wants to quit, he can still gamble if he doesn't have any bits anymore because he can claim with faucets.