The only reason I would spend my campaign payment on gambling no matter or regardless of where it is paid is if i don't have any very important thing to do with the money, then in a situation like this, receiving the payment on a casino is even preferred as it saves me the stress of trying to deposit to the casino again.

But in times when I have a lot of things requiring financial attention and I imagined that my campaign payment would go along way in helping me settle those financial issues, I would withdraw the money even if it was paid into my casino account.
I think it's once (if I still remember correctly) I lost my entire campaign fund on gambling because it was paid directly to my account on the casino, since then, I sometimes would spend a small part of the fund, then withdraw the rest if I am not winning, but In times of financial issues, I withdraw without spending any part of the fund on any game.