The reasons why people try to bank their money with another account was because they do not want to gamble with all of their money but they also want to make sure they have a certain amount of money to gamble on that session.

For example, let's make the numbers up and say that there is this one dude who will play 100 dollars per day for 1 week, he deposits 700 dollars because he doesn't want to put in 100 dollars every day, there is no need for something like that. What can he do if he wins? Continue to gamble?

He said he will only wager 100 dollars per day, so even if he wins all of it or some of it, there will be some excess, he probably will not lose all of it, so lets assume he has 20 dollars extra, he puts it back to the vault. He does this for 7 days straight and maybe he could be higher than anticipated? That is how it would work with the vault.

I also think that vault could bring in some profit as well if wolf.bet really wants to go to that route for more money. Think about it as a bankroll for the casino, investment from the people, you can either make it a yearly thing that will give people a fixed amount of profit as long as they keep it there, or maybe it could be simply just bankrolling the casino and making a profit when casino makes a profit or losing when casino loses, both has advantages and disadvantages for both casino and the investors.

I don't know if wolf.bet needs money but considering they have dropped the prize from 1000 dollars to 500 dollars, I would say it is quite possible that they could actually take advantage of that money as well and work with it to get wolf.bet bigger as well.