My instinct says that there are multiple reasons for this rule.
1. It allows support to immediately determine that the player has met the rules, rather than spending time finding entry and exit points. Considering 32Red’s fast support, I think this is a small price to pay.
2. Normally, bonuses are credited very quickly in the first place. Once you apply for the bonus I would be surprised if it takes more than an hour to have it put into your account, except on weekends.
3. Theoretically, it also allows the casino to verify the eligibility of the person applying for the bonus – call it a security check if you like – which then makes it much easier to deal with future cashouts, rather than going through this whole process only when a cashout is due and thus unnecessarily upsetting players. It’s one thing to make them wait an hour before getting their bonus. It’s another thing entirely to make them wait a long time to receive their cashout.
Look at the big picture. Waiting a day or more for a bonus to be applied – yeah, that would kind of suck. 32Red does it on a very fast basis. And also, compare it to having to wait for a PIN number from a Cryptologic casino before being allowed to cash out – that’s at least a WEEK.