I think the only players who should be prevented from depositing are those who have engaged in fraudulent practices, such as using multiple identities, etc.
If casinos want to also utilize a list of customers ineligible for bonuses, that could be based on players who routinely open an account, meet the terms and conditions minimally, and move on to another casino. These customers should still be allowed to deposit though.
For the record, I’m certain I don’t belong in the first list, and sincerely think I shouldn’t be on the second either.