I don`t see any problem to deposit money to casino i prefer.
When casino give you money to your bankroll in this casino it is not fair as for me. I made the job, they paid me for it. I decide how to spend these money myself. To be fair, mostly i can withdraw money, but it is one additional step i have to do. For somebody it would be more easier to spend money right now in this casino.
But the same time, everybody of us can read the campaign description and if we participate it means that we agree with such conditions.
The decision to pay for the campaign was made by mutual agreement between the manager and the casino itself... so this rule is clear.
Payments to casino accounts are not a problem and there are no restrictions on playing you can withdraw whenever you want that's what I've seen in several active campaigns.
It could be that signature campaigns pay into casino accounts to encourage players to keep playing... but the decision is still in your own hands.